From 8a8d69032038c8ae837eb59ed6f2cfa55ee1c0d7 Mon Sep 17 00:00:00 2001
From: Dongsu Park <dongsu@endocode.com>
Date: Tue, 26 Jul 2016 16:54:41 +0200
Subject: [PATCH] agent: make TestUnitStatePublisher wait for each goroutine to
 finish

TestUnitStatePublisherRunWithDelays() has not exactly initiated each
service sequentially, but let it run in parallel. That's why the unit
test sometimes fails with messages like:

```
--- FAIL: TestUnitStatePublisherRunWithDelays-2 (0.00 seconds)
    unit_state_test.go:626: bad published UnitStates:
    got []string{"0.service", "2.service", "4.service", "1.service", "3.service"},
    want []string{"0.service", "1.service", "2.service", "3.service", "4.service"}
    unit_state_test.go:640: bad published UnitStates:
    got []string{"0.service", "2.service", "4.service", "1.service", "3.service"},
    want []string{"0.service", "1.service", "2.service", "3.service", "4.service"}
    unit_state_test.go:658: bad UnitStates:
    got []string{"foo.service", "baz.service", "bar.service"},
    want []string{"foo.service", "bar.service", "baz.service"}
```

To fix that, for each goroutine, check that the channel toPublish
contains the expected unit name.

Suggested by @jonboulle
Fixes https://github.com/coreos/fleet/issues/1248
---
 agent/unit_state_test.go | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/agent/unit_state_test.go b/agent/unit_state_test.go
index 0a239c623..710571404 100644
--- a/agent/unit_state_test.go
+++ b/agent/unit_state_test.go
@@ -625,13 +625,36 @@ func TestUnitStatePublisherRunWithDelays(t *testing.T) {
 		)
 	}
 
+	waitUnitToPublish := func(uName string) {
+		select {
+		case name := <-usp.toPublish:
+			if name != uName {
+				t.Errorf("unexpected name on toPublish channel: %v", name)
+			}
+		case <-time.After(time.Second):
+			t.Fatal("did not receive on toPublish channel as expected")
+		}
+	}
+
 	// now queue some more unit states for publishing - expect them to hang
-	go usp.queueForPublish("foo.service", &unit.UnitState{UnitName: "foo.service", ActiveState: "active"})
+	go usp.queueForPublish("foo.service", &unit.UnitState{
+		UnitName:    "foo.service",
+		ActiveState: "active",
+	})
+	waitUnitToPublish("foo.service")
+
 	go usp.queueForPublish("bar.service", &unit.UnitState{})
+	waitUnitToPublish("bar.service")
+
 	go usp.queueForPublish("baz.service", &unit.UnitState{})
+	waitUnitToPublish("baz.service")
 
 	// re-queue one of the states; this should replace the above
-	go usp.queueForPublish("foo.service", &unit.UnitState{UnitName: "foo.service", ActiveState: "inactive"})
+	go usp.queueForPublish("foo.service", &unit.UnitState{
+		UnitName:    "foo.service",
+		ActiveState: "inactive",
+	})
+	waitUnitToPublish("foo.service")
 
 	// wait for all publish workers to start
 	wgs.Wait()