|  | // Copyright (c) 2012 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_NULL_TASK_RUNNER_H_ | 
|  | #define BASE_TEST_NULL_TASK_RUNNER_H_ | 
|  |  | 
|  | #include "base/callback.h" | 
|  | #include "base/compiler_specific.h" | 
|  | #include "base/macros.h" | 
|  | #include "base/single_thread_task_runner.h" | 
|  |  | 
|  | namespace base { | 
|  |  | 
|  | // Helper class for tests that need to provide an implementation of a | 
|  | // *TaskRunner class but don't actually care about tasks being run. | 
|  |  | 
|  | class NullTaskRunner : public base::SingleThreadTaskRunner { | 
|  | public: | 
|  | NullTaskRunner(); | 
|  |  | 
|  | bool PostDelayedTask(const Location& from_here, | 
|  | base::OnceClosure task, | 
|  | base::TimeDelta delay) override; | 
|  | bool PostNonNestableDelayedTask(const Location& from_here, | 
|  | base::OnceClosure task, | 
|  | base::TimeDelta delay) override; | 
|  | // Always returns true to avoid triggering DCHECKs. | 
|  | bool RunsTasksInCurrentSequence() const override; | 
|  |  | 
|  | protected: | 
|  | ~NullTaskRunner() override; | 
|  |  | 
|  | DISALLOW_COPY_AND_ASSIGN(NullTaskRunner); | 
|  | }; | 
|  |  | 
|  | }  // namespace base | 
|  |  | 
|  | #endif  // BASE_TEST_NULL_TASK_RUNNER_H_ |