snapshot of https://github.com/grpc/grpc-go.git (master, 2026-09-15; blobs > 131072B omitted)

internal/testutils/blocking_context_dialer_test.go

@@ -0,0 +1,214 @@
+/*
+ *
+ * Copyright 2024 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package testutils
+
+import (
+	"context"
+	"errors"
+	"testing"
+	"time"
+)
+
+const (
+	testTimeout      = 5 * time.Second
+	testShortTimeout = 10 * time.Millisecond
+)
+
+func (s) TestBlockingDialer_NoHold(t *testing.T) {
+	lis, err := LocalTCPListener()
+	if err != nil {
+		t.Fatalf("Failed to listen: %v", err)
+	}
+	defer lis.Close()
+
+	d := NewBlockingDialer()
+
+	// This should not block.
+	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+	defer cancel()
+	conn, err := d.DialContext(ctx, lis.Addr().String())
+	if err != nil {
+		t.Fatalf("Failed to dial: %v", err)
+	}
+	conn.Close()
+}
+
+func (s) TestBlockingDialer_HoldWaitResume(t *testing.T) {
+	lis, err := LocalTCPListener()
+	if err != nil {
+		t.Fatalf("Failed to listen: %v", err)
+	}
+	defer lis.Close()
+
+	d := NewBlockingDialer()
+	h := d.Hold(lis.Addr().String())
+
+	if h.IsStarted() {
+		t.Fatalf("hold.IsStarted() = true, want false")
+	}
+
+	done := make(chan struct{})
+	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+	defer cancel()
+	go func() {
+		defer close(done)
+		conn, err := d.DialContext(ctx, lis.Addr().String())
+		if err != nil {
+			t.Errorf("BlockingDialer.DialContext() got error: %v, want success", err)
+			return
+		}
+
+		if !h.IsStarted() {
+			t.Errorf("hold.IsStarted() = false, want true")
+		}
+		conn.Close()
+	}()
+
+	// This should block until the goroutine above is scheduled.
+	if !h.Wait(ctx) {
+		t.Fatalf("Timeout while waiting for a connection attempt to %q", h.addr)
+	}
+
+	if !h.IsStarted() {
+		t.Errorf("hold.IsStarted() = false, want true")
+	}
+
+	select {
+	case <-done:
+		t.Fatalf("Expected dialer to be blocked.")
+	case <-time.After(testShortTimeout):
+	}
+
+	h.Resume() // Unblock the above goroutine.
+
+	select {
+	case <-done:
+	case <-ctx.Done():
+		t.Errorf("Timeout waiting for connection attempt to resume.")
+	}
+}
+
+func (s) TestBlockingDialer_HoldWaitFail(t *testing.T) {
+	lis, err := LocalTCPListener()
+	if err != nil {
+		t.Fatalf("Failed to listen: %v", err)
+	}
+	defer lis.Close()
+
+	d := NewBlockingDialer()
+	h := d.Hold(lis.Addr().String())
+
+	wantErr := errors.New("test error")
+
+	dialError := make(chan error)
+	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
+	defer cancel()
+	go func() {
+		_, err := d.DialContext(ctx, lis.Addr().String())
+		dialError <- err
+	}()
+
+	if !h.Wait(ctx) {
+		t.Fatal("Timeout while waiting for a connection attempt to " + h.addr)
+	}
+	select {
+	case err = <-dialError:
+		t.Errorf("DialContext got unblocked with err %v. Want DialContext to still be blocked after Wait()", err)
+	case <-time.After(testShortTimeout):
+	}
+
+	h.Fail(wantErr)
+
+	select {
+	case err = <-dialError:
+		if !errors.Is(err, wantErr) {
+			t.Errorf("BlockingDialer.DialContext() after Fail(): got error %v, want %v", err, wantErr)
+		}
+	case <-ctx.Done():
+		t.Errorf("Timeout waiting for connection attempt to fail.")
+	}
+}
+
+func (s) TestBlockingDialer_ContextCanceled(t *testing.T) {
+	lis, err := LocalTCPListener()
+	if err != nil {
+		t.Fatalf("Failed to listen: %v", err)
+	}
+	defer lis.Close()
+
+	d := NewBlockingDialer()
+	h := d.Hold(lis.Addr().String())
+
+	dialErr := make(chan error)
+	testCtx, cancel := context.WithTimeout(context.Background(), testTimeout)
+	defer cancel()
+
+	ctx, cancel := context.WithCancel(testCtx)
+	defer cancel()
+	go func() {
+		_, err := d.DialContext(ctx, lis.Addr().String())
+		dialErr <- err
+	}()
+	if !h.Wait(testCtx) {
+		t.Errorf("Timeout while waiting for a connection attempt to %q", h.addr)
+	}
+
+	cancel()
+
+	select {
+	case err = <-dialErr:
+		if !errors.Is(err, context.Canceled) {
+			t.Errorf("BlockingDialer.DialContext() after context cancel: got error %v, want %v", err, context.Canceled)
+		}
+	case <-testCtx.Done():
+		t.Errorf("Timeout while waiting for Wait to return.")
+	}
+
+	h.Resume() // noop, just make sure nothing bad happen.
+}
+
+func (s) TestBlockingDialer_CancelWait(t *testing.T) {
+	lis, err := LocalTCPListener()
+	if err != nil {
+		t.Fatalf("Failed to listen: %v", err)
+	}
+	defer lis.Close()
+
+	d := NewBlockingDialer()
+	h := d.Hold(lis.Addr().String())
+
+	testCtx, cancel := context.WithTimeout(context.Background(), testTimeout)
+	defer cancel()
+
+	ctx, cancel := context.WithCancel(testCtx)
+	cancel()
+	done := make(chan struct{})
+	go func() {
+		if h.Wait(ctx) {
+			t.Errorf("Expected cancel to return false when context expires")
+		}
+		done <- struct{}{}
+	}()
+
+	select {
+	case <-done:
+	case <-testCtx.Done():
+		t.Errorf("Timeout while waiting for Wait to return.")
+	}
+}