Implements TestMessageLoop that flushes pending tasks on destruction.

base/test/test_message_loop.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef BASE_TEST_TEST_MESSAGE_LOOP_H_
+#define BASE_TEST_TEST_MESSAGE_LOOP_H_
+
+#include "base/message_loop/message_loop.h"
+
+namespace base {
+
+// TestMessageLoop is a convenience class for unittests that need to create a
+// message loop without a real thread backing it. For most tests,
+// it is sufficient to just instantiate TestMessageLoop as a member variable.
+//
+// TestMessageLoop will attempt to drain the underlying MessageLoop on
+// destruction for clean teardown of tests.
+class TestMessageLoop {
+ public:
+  TestMessageLoop();
+  explicit TestMessageLoop(MessageLoop::Type type);
+  ~TestMessageLoop();
+
+ private:
+  MessageLoop loop_;
+};
+
+}  // namespace base
+
+#endif  // BASE_TEST_TEST_MESSAGE_LOOP_H_