test: fix flaky test ClientSendsAGoAway (#7224)

Author: aranjans

test/goaway_test.go

@@ -770,36 +770,20 @@ func (s) TestClientSendsAGoAway(t *testing.T) {
 	if err != nil {
 		t.Fatalf("error listening: %v", err)
 	}
-	ctCh := testutils.NewChannel()
+	defer lis.Close()
+	goAwayReceived := make(chan struct{})
+	errCh := make(chan error)
 	go func() {
 		conn, err := lis.Accept()
 		if err != nil {
 			t.Errorf("error in lis.Accept(): %v", err)
 		}
 		ct := newClientTester(t, conn)
-		ctCh.Send(ct)
-	}()
-	defer lis.Close()
-
-	cc, err := grpc.Dial(lis.Addr().String(), grpc.WithTransportCredentials(insecure.NewCredentials()))
-	if err != nil {
-		t.Fatalf("error dialing: %v", err)
-	}
-
-	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
-	defer cancel()
-
-	val, err := ctCh.Receive(ctx)
-	if err != nil {
-		t.Fatalf("timeout waiting for client transport (should be given after http2 creation)")
-	}
-	ct := val.(*clientTester)
-	goAwayReceived := make(chan struct{})
-	errCh := make(chan error)
-	go func() {
+		defer ct.conn.Close()
 		for {
 			f, err := ct.fr.ReadFrame()
 			if err != nil {
+				errCh <- fmt.Errorf("error reading frame: %v", err)
 				return
 			}
 			switch fr := f.(type) {
@@ -808,6 +792,7 @@ func (s) TestClientSendsAGoAway(t *testing.T) {
 				if fr.ErrCode == http2.ErrCodeNo {
 					t.Logf("GoAway received from client")
 					close(goAwayReceived)
+					return
 				}
 			default:
 				t.Errorf("server tester received unexpected frame type %T", f)
@@ -816,8 +801,18 @@ func (s) TestClientSendsAGoAway(t *testing.T) {
 			}
 		}
 	}()
+
+	cc, err := grpc.NewClient(lis.Addr().String(), grpc.WithTransportCredentials(insecure.NewCredentials()))
+	if err != nil {
+		t.Fatalf("error dialing: %v", err)
+	}
+	cc.Connect()
+
+	ctx, cancel := context.WithTimeout(context.Background(), defaultTestTimeout)
+	defer cancel()
+
+	testutils.AwaitState(ctx, t, cc, connectivity.Ready)
 	cc.Close()
-	defer ct.conn.Close()
 	select {
 	case <-goAwayReceived:
 	case err := <-errCh: