http2: modernize TestTransportRoundtripCloseOnWriteError

Rewrite this test to use a testClientConn and fake network, allowing us to inject its network error into the fake net rather than by twiddling the client connection internals. Change-Id: Idcd96498ceaee701ad0c053dc0c6ce74701cc182 Reviewed-on: https://go-review.googlesource.com/c/net/+/701006 Auto-Submit: Damien Neil <dneil@google.com> Reviewed-by: Nicholas Husin <husin@google.com> Reviewed-by: Nicholas Husin <nsh@golang.org> LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

Author: neild

http2/clientconn_test.go

@@ -194,6 +194,13 @@ func (tc *testClientConn) closeWrite() {
 tc.netconn.Close()
 }
 
+// closeWrite causes the net.Conn used by the ClientConn to return a error
+// from Write calls.
+func (tc *testClientConn) closeWriteWithError(err error) {
+tc.netconn.loc.setReadError(io.EOF)
+tc.netconn.loc.setWriteError(err)
+}
+
 // testRequestBody is a Request.Body for use in tests.
 type testRequestBody struct {
 tc *testClientConn

http2/transport_test.go

@@ -4243,35 +4243,28 @@ func TestTransportNewClientConnCloseOnWriteError(t *testing.T) {
 }
 
 func TestTransportRoundtripCloseOnWriteError(t *testing.T) {
-req, err := http.NewRequest("GET", "https://dummy.tld/", nil)
-if err != nil {
-t.Fatal(err)
-}
-ts := newTestServer(t, func(w http.ResponseWriter, r *http.Request) {})
+synctestTest(t, testTransportRoundtripCloseOnWriteError)
+}
+func testTransportRoundtripCloseOnWriteError(t testing.TB) {
+tc := newTestClientConn(t)
+tc.greet()
 
-tr := &Transport{TLSClientConfig: tlsConfigInsecure}
-defer tr.CloseIdleConnections()
-ctx := context.Background()
-cc, err := tr.dialClientConn(ctx, ts.Listener.Addr().String(), false)
-if err != nil {
-t.Fatal(err)
-}
+body := tc.newRequestBody()
+body.writeBytes(1)
+req, _ := http.NewRequest("GET", "https://dummy.tld/", body)
+rt := tc.roundTrip(req)
 
 writeErr := errors.New("write error")
-cc.wmu.Lock()
-cc.werr = writeErr
-cc.wmu.Unlock()
+tc.closeWriteWithError(writeErr)
 
-_, err = cc.RoundTrip(req)
-if err != writeErr {
-t.Fatalf("expected %v, got %v", writeErr, err)
+body.writeBytes(1)
+if err := rt.err(); err != writeErr {
+t.Fatalf("RoundTrip error %v, want %v", err, writeErr)
 }
 
-cc.mu.Lock()
-closed := cc.closed
-cc.mu.Unlock()
-if !closed {
-t.Fatal("expected closed")
+rt2 := tc.roundTrip(req)
+if err := rt2.err(); err != errClientConnUnusable {
+t.Fatalf("RoundTrip error %v, want errClientConnUnusable", err)
 }
 }