interna/middleware: synchronize instead of sleeping in TestSetAndLoadExperiments
Fixes #62530.
Change-Id: I06516921c170a606e9fe663b6cd8a248cd891a73
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/526173
TryBot-Result: Gopher Robot <gobot@golang.org>
Commit-Queue: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
kokoro-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
Run-TryBot: Bryan Mills <bcmills@google.com>
diff --git a/internal/middleware/experiment_test.go b/internal/middleware/experiment_test.go
index 81687ef..c88dc73 100644
--- a/internal/middleware/experiment_test.go
+++ b/internal/middleware/experiment_test.go
@@ -21,16 +21,26 @@
)
func TestSetAndLoadExperiments(t *testing.T) {
- ctx := context.Background()
+ ctx, cancel := context.WithCancel(context.Background())
+ defer cancel()
+
const testFeature = "test-feature"
+
var mu sync.Mutex
testExps := []*internal.Experiment{{Name: testFeature, Rollout: 100}}
- testGetter := func(context.Context) ([]*internal.Experiment, error) {
+ getterStarted := make(chan bool, 1)
+ testGetter := func(ctx context.Context) ([]*internal.Experiment, error) {
+ select {
+ case <-ctx.Done():
+ return nil, ctx.Err()
+ case getterStarted <- true:
+ }
+
mu.Lock()
defer mu.Unlock()
return testExps, nil
}
- experimenter, err := NewExperimenter(ctx, 10*time.Millisecond, testGetter, nil)
+ experimenter, err := NewExperimenter(ctx, 1*time.Millisecond, testGetter, nil)
if err != nil {
t.Fatal(err)
}
@@ -69,7 +79,20 @@
mu.Lock()
testExps = []*internal.Experiment{{Name: testFeature, Rollout: 0}}
mu.Unlock()
- time.Sleep(100 * time.Millisecond)
+
+ // Wait for the getter to run for the third time.
+ // The first run happened before NewExperimenter returned,
+ // and filled the channel buffer.
+ // The second run happens at some point after we clear the buffer here.
+ <-getterStarted
+ // When we receive again, we know the second run has started.
+ <-getterStarted
+ // However, we don't know for certain that the poller has posted the result
+ // of that run, *until* it has started the third run.
+ <-getterStarted
+ // Now we know that the second run — which happened after we stored to testExps —
+ // has completed, and its result should be visible.
+
makeRequest(t)
if featureIsOn {
t.Fatalf("experiment %q should not be active", testFeature)
