Replace TestSimpleTaskRunner::GetPendingTasks with TakePendingTasks

base/test/test_simple_task_runner.h

 // 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_TEST_SIMPLE_TASK_RUNNER_H_
 #define BASE_TEST_TEST_SIMPLE_TASK_RUNNER_H_
 
 #include <deque>
 
 #include "base/compiler_specific.h"
@@ skipping 33 matching lines @@
   // SingleThreadTaskRunner implementation.
   bool PostDelayedTask(const tracked_objects::Location& from_here,
                        const Closure& task,
                        TimeDelta delay) override;
   bool PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
                                   const Closure& task,
                                   TimeDelta delay) override;
 
   bool RunsTasksOnCurrentThread() const override;
 
-  std::deque<TestPendingTask> GetPendingTasks() const;
+  std::deque<TestPendingTask> TakePendingTasks();
   size_t NumPendingTasks() const;
   bool HasPendingTask() const;
   base::TimeDelta NextPendingTaskDelay() const;
+  base::TimeDelta FinalPendingTaskDelay() const;
+  tracked_objects::Location GetPendingTaskLocationAt(size_t index) const;

[danakj, 2016/09/21 22:16:59]

I don't think this is safe, in the time between NumPendingTasks and the call to
this, the index may not be valid anymore since you're not holding the |lock_|?

[pastarmovj, 2016/09/22 08:12:51]

+1 

Maybe take a snapshot of the deque with TakePendingTasks and assert its size and
contents instead. Then you don't need this function at all.

[tzik, 2016/09/29 05:58:04]

Ah, right. I updated it to return a base::Optional. Other data races should be
handled by the caller.

 
   // Clears the queue of pending tasks without running them.
   void ClearPendingTasks();
 
   // Runs each current pending task in order and clears the queue. Tasks posted
   // by the tasks that run within this call do not run within this call. Can
   // only be called on the thread that created this TestSimpleTaskRunner.
   void RunPendingTasks();
 
   // Runs pending tasks until the queue is empty. Can only be called on the
@@ skipping 11 matching lines @@
   mutable Lock lock_;
 
   std::deque<TestPendingTask> pending_tasks_;
 
   DISALLOW_COPY_AND_ASSIGN(TestSimpleTaskRunner);
 };
 
 }  // namespace base
 
 #endif  // BASE_TEST_TEST_SIMPLE_TASK_RUNNER_H_