test & testutils: prevent goroutine leaks in test functions (#3133)

internal/testutils/pipe_listener_test.go

@@ -27,7 +27,7 @@ import (
 
 func TestPipeListener(t *testing.T) {
 	pl := testutils.NewPipeListener()
-	recvdBytes := make(chan []byte)
+	recvdBytes := make(chan []byte, 1)
 	const want = "hello world"
 
 	go func() {

test/bufconn/bufconn_test.go

@@ -96,7 +96,7 @@ func TestConn(t *testing.T) {
 
 func TestConnCloseWithData(t *testing.T) {
 	lis := Listen(7)
-	errChan := make(chan error)
+	errChan := make(chan error, 1)
 	var lisConn net.Conn
 	go func() {
 		var err error
@@ -199,7 +199,7 @@ func TestCloseWhileAccepting(t *testing.T) {
 }
 
 func TestDeadline(t *testing.T) {
-	sig := make(chan error)
+	sig := make(chan error, 2)
 	blockingWrite := func(conn net.Conn) {
 		_, err := conn.Write([]byte("0123456789"))
 		sig <- err

test/end2end_test.go

@@ -4694,7 +4694,7 @@ func testClientResourceExhaustedCancelFullDuplex(t *testing.T, e env) {
 		resp := &testpb.StreamingOutputCallResponse{
 			Payload: payload,
 		}
-		ce := make(chan error)
+		ce := make(chan error, 1)
 		go func() {
 			var err error
 			for {