unjs · kricsleo · May 5, 2025
diff --git a/src/utils.ts b/src/utils.ts
@@ -106,9 +106,7 @@ function interopDefault(mod: any): any {
 
   const def = mod.default;
   const defType = typeof def;
-  if (def === null || def === undefined) {
-    return mod;
-  }
+  const defIsNil = def === null || def === undefined;
   const defIsObj = defType === "object" || defType === "function";

   return new Proxy(mod, {
@@ -117,7 +115,7 @@ function interopDefault(mod: any): any {
         return true;
       }
       if (prop === "default") {
-        return def;
+        return defIsNil ? mod : def;
       }
       if (Reflect.has(target, prop)) {
         return Reflect.get(target, prop, receiver);

diff --git a/test/fixtures/require-esm/_dist/esm-transpiled-cjs.js b/test/fixtures/require-esm/_dist/esm-transpiled-cjs.js
@@ -0,0 +1,37 @@
+/**
+ * Transpiled by esbuild: https://hyrious.me/esbuild-repl/?version=0.25.3&t=export+function+fn%28%29+%7B%7D&o=--format%3Dcjs
+ *
+ * Original ESM code:
+ * ```js
+ * export function fn() {}
+ * ```
+ *
+ * Transpiled CJS code: ↓↓↓
+ */
+var __defProp = Object.defineProperty;
+var __getOwnPropDesc = Object.getOwnPropertyDescriptor;
+var __getOwnPropNames = Object.getOwnPropertyNames;
+var __hasOwnProp = Object.prototype.hasOwnProperty;
+var __export = (target, all) => {
+  for (var name in all)
+    __defProp(target, name, { get: all[name], enumerable: true });
+};
+var __copyProps = (to, from, except, desc) => {
+  if ((from && typeof from === "object") || typeof from === "function") {
+    for (let key of __getOwnProp
EB82
Names(from))
+      if (!__hasOwnProp.call(to, key) && key !== except)
+        __defProp(to, key, {
+          get: () => from[key],
+          enumerable: !(desc = __getOwnPropDesc(from, key)) || desc.enumerable,
+        });
+  }
+  return to;
+};
+var __toCommonJS = (mod) =>
+  __copyProps(__defProp({}, "__esModule", { value: true }), mod);
+var stdin_exports = {};
+__export(stdin_exports, {
+  fn: () => fn,
+});
+module.exports = __toCommonJS(stdin_exports);
+function fn() {}
diff --git a/test/fixtures/require-esm/_dist/esm.js b/test/fixtures/require-esm/_dist/esm.js
@@ -1,3 +1,4 @@
 import fn from "./fn.js";
+import transpiled from "./esm-transpiled-cjs.js";
 import file from "./file";
-export default { fn, file };
+export default { fn, fn2: transpiled.fn, file };
diff --git a/test/fixtures/require-esm/index.cjs b/test/fixtures/require-esm/index.cjs
@@ -8,7 +8,7 @@ async function run() {
     mod = await jiti.import("./_dist/esm.js");
   }
   mod = mod.default;
-  if (typeof mod.fn === "function") {
+  if (typeof mod.fn === "function" && typeof mod.fn2 === "function") {
     console.log("Works!");
     return;
   }