Merge pull request etcd-io#12538 from lzhfromustc/12_9_GoroutineLeak

test: change channel operations to avoid potential goroutine leaks

pkg/transport/timeout_dialer_test.go

@@ -22,14 +22,14 @@ import (
 
 func TestReadWriteTimeoutDialer(t *testing.T) {
 	stop := make(chan struct{})
-	defer func() {
-		stop <- struct{}{}
-	}()
 
 	ln, err := net.Listen("tcp", "127.0.0.1:0")
 	if err != nil {
 		t.Fatalf("unexpected listen error: %v", err)
 	}
+	defer func() {
+		stop <- struct{}{}
+	}()
 	ts := testBlockingServer{ln, 2, stop}
 	go ts.Start(t)
 

server/etcdserver/server_test.go

@@ -213,7 +213,7 @@ func TestApplyRepeat(t *testing.T) {
 	// wait for conf change message
 	act, err := n.Wait(1)
 	// wait for stop message (async to avoid deadlock)
-	stopc := make(chan error)
+	stopc := make(chan error, 1)
 	go func() {
 		_, werr := n.Wait(1)
 		stopc <- werr

tests/integration/clientv3/experimental/recipes/v3_double_barrier_test.go

@@ -36,6 +36,7 @@ func TestDoubleBarrier(t *testing.T) {
 
 	b := recipe.NewDoubleBarrier(session, "test-barrier", waiters)
 	donec := make(chan struct{})
+	defer close(donec)
 	for i := 0; i < waiters-1; i++ {
 		go func() {
 			session, err := concurrency.NewSession(clus.RandClient())
@@ -48,17 +49,17 @@ func TestDoubleBarrier(t *testing.T) {
 			if err := bb.Enter(); err != nil {
 				t.Errorf("could not enter on barrier (%v)", err)
 			}
-			donec <- struct{}{}
+			<-donec
 			if err := bb.Leave(); err != nil {
 				t.Errorf("could not leave on barrier (%v)", err)
 			}
-			donec <- struct{}{}
+			<-donec
 		}()
 	}
 
 	time.Sleep(10 * time.Millisecond)
 	select {
-	case <-donec:
+	case donec <- struct{}{}:
 		t.Fatalf("barrier did not enter-wait")
 	default:
 	}
@@ -72,13 +73,13 @@ func TestDoubleBarrier(t *testing.T) {
 		select {
 		case <-timerC:
 			t.Fatalf("barrier enter timed out")
-		case <-donec:
+		case donec <- struct{}{}:
 		}
 	}
 
 	time.Sleep(10 * time.Millisecond)
 	select {
-	case <-donec:
+	case donec <- struct{}{}:
 		t.Fatalf("barrier did not leave-wait")
 	default:
 	}
@@ -89,7 +90,7 @@ func TestDoubleBarrier(t *testing.T) {
 		select {
 		case <-timerC:
 			t.Fatalf("barrier leave timed out")
-		case <-donec:
+		case donec <- struct{}{}:
 		}
 	}
 }
@@ -100,6 +101,7 @@ func TestDoubleBarrierFailover(t *testing.T) {
 
 	waiters := 10
 	donec := make(chan struct{})
+	defer close(donec)
 
 	s0, err := concurrency.NewSession(clus.Client(0))
 	if err != nil {
@@ -118,7 +120,7 @@ func TestDoubleBarrierFailover(t *testing.T) {
 		if berr := b.Enter(); berr != nil {
 			t.Errorf("could not enter on barrier (%v)", berr)
 		}
-		donec <- struct{}{}
+		<-donec
 	}()
 
 	for i := 0; i < waiters-1; i++ {
@@ -127,16 +129,16 @@ func TestDoubleBarrierFailover(t *testing.T) {
 			if berr := b.Enter(); berr != nil {
 				t.Errorf("could not enter on barrier (%v)", berr)
 			}
-			donec <- struct{}{}
+			<-donec
 			b.Leave()
-			donec <- struct{}{}
+			<-donec
 		}()
 	}
 
 	// wait for barrier enter to unblock
 	for i := 0; i < waiters; i++ {
 		select {
-		case <-donec:
+		case donec <- struct{}{}:
 		case <-time.After(10 * time.Second):
 			t.Fatalf("timed out waiting for enter, %d", i)
 		}
@@ -148,7 +150,7 @@ func TestDoubleBarrierFailover(t *testing.T) {
 	// join on rest of waiters
 	for i := 0; i < waiters-1; i++ {
 		select {
-		case <-donec:
+		case donec <- struct{}{}:
 		case <-time.After(10 * time.Second):
 			t.Fatalf("timed out waiting for leave, %d", i)
 		}

tests/integration/clientv3/kv_test.go

@@ -778,7 +778,7 @@ func TestKVPutFailGetRetry(t *testing.T) {
 		t.Fatalf("got success on disconnected put, wanted error")
 	}
 
-	donec := make(chan struct{})
+	donec := make(chan struct{}, 1)
 	go func() {
 		// Get will fail, but reconnect will trigger
 		gresp, gerr := kv.Get(context.TODO(), "foo")

tests/integration/v2_http_kv_test.go

@@ -954,7 +954,7 @@ func TestV2WatchKeyInDir(t *testing.T) {
 	tc := NewTestClient()
 
 	var body map[string]interface{}
-	c := make(chan bool)
+	c := make(chan bool, 1)
 
 	// Create an expiring directory
 	v := url.Values{}

tests/integration/v3_watch_test.go

@@ -1097,7 +1097,7 @@ func TestV3WatchWithFilter(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	recv := make(chan *pb.WatchResponse)
+	recv := make(chan *pb.WatchResponse, 1)
 	go func() {
 		// check received PUT
 		resp, rerr := ws.Recv()