Merge pull request #17925 from cpuguy83/fix_locker_unit_tests

Use timeouts instead of relying on runtime.GoSched

locker/locker_test.go

@@ -1,8 +1,8 @@
 package locker
 
 import (
-	"runtime"
 	"testing"
+	"time"
 )
 
 func TestLockCounter(t *testing.T) {
@@ -34,7 +34,21 @@ func TestLockerLock(t *testing.T) {
 		close(chDone)
 	}()
 
-	runtime.Gosched()
+	chWaiting := make(chan struct{})
+	go func() {
+		for range time.Tick(1 * time.Millisecond) {
+			if ctr.count() == 1 {
+				close(chWaiting)
+				break
+			}
+		}
+	}()
+
+	select {
+	case <-chWaiting:
+	case <-time.After(3 * time.Second):
+		t.Fatal("timed out waiting for lock waiters to be incremented")
+	}
 
 	select {
 	case <-chDone:
@@ -42,26 +56,15 @@ func TestLockerLock(t *testing.T) {
 	default:
 	}
 
-	if ctr.count() != 1 {
-		t.Fatalf("expected waiters to be 1, got: %d", ctr.count())
-	}
-
 	if err := l.Unlock("test"); err != nil {
 		t.Fatal(err)
 	}
-	runtime.Gosched()
 
 	select {
 	case <-chDone:
-	default:
+	case <-time.After(3 * time.Second):
-		// one more time just to be sure
-		runtime.Gosched()
-		select {
-		case <-chDone:
-		default:
 		t.Fatalf("lock should have completed")
 	}
-	}
 
 	if ctr.count() != 0 {
 		t.Fatalf("expected waiters to be 0, got: %d", ctr.count())
@@ -80,11 +83,9 @@ func TestLockerUnlock(t *testing.T) {
 		close(chDone)
 	}()
 
-	runtime.Gosched()
-
 	select {
 	case <-chDone:
-	default:
+	case <-time.After(3 * time.Second):
 		t.Fatalf("lock should not be blocked")
 	}
 }