TaskScheduler [11] Support ExecutionMode::SINGLE_THREADED.

base/task_scheduler/scheduler_worker_thread_unittest.cc

 // 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.
 
 #include "base/task_scheduler/scheduler_worker_thread.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <vector>
@@ skipping 26 matching lines @@
     worker_thread_ = SchedulerWorkerThread::Create(
         ThreadPriority::NORMAL,
         WrapUnique(new TestSchedulerWorkerThreadDelegate(this)),
         &task_tracker_);
     ASSERT_TRUE(worker_thread_);
     main_entry_called_.Wait();
   }
 
   void TearDown() override {
     worker_thread_->JoinForTesting();
+
+    {
+      AutoSchedulerLock auto_lock(main_entry_worker_thread_lock_);
+      EXPECT_EQ(worker_thread_.get(), main_entry_worker_thread_);
+    }
   }
 
   size_t TasksPerSequence() const { return GetParam(); }
 
   // Wait until GetWork() has been called |num_get_work| times.
   void WaitForNumGetWork(size_t num_get_work) {
     AutoSchedulerLock auto_lock(lock_);
     while (num_get_work_ < num_get_work)
       num_get_work_cv_->Wait();
   }
@@ skipping 27 matching lines @@
   std::unique_ptr<SchedulerWorkerThread> worker_thread_;
 
  private:
   class TestSchedulerWorkerThreadDelegate
       : public SchedulerWorkerThread::Delegate {
    public:
     TestSchedulerWorkerThreadDelegate(TaskSchedulerWorkerThreadTest* outer)
         : outer_(outer) {}
 
     // SchedulerWorkerThread::Delegate:
-    void OnMainEntry() override {
+    void OnMainEntry(SchedulerWorkerThread* worker_thread) override {
+      {
+        AutoSchedulerLock auto_lock(outer_->main_entry_worker_thread_lock_);
+        outer_->main_entry_worker_thread_ = worker_thread;

[gab, 2016/04/26 11:46:27]

Why can't this directly compare to |worker_thread_| instead of waiting until
TearDown()? Is it because of thread-safety with SetUp()? Feels we could make
this work with some synchronization logic, feels weird to have this store state
merely to verify it in TearDown()..

[fdoray, 2016/04/26 14:56:47]

OnMainEntry() may be called before |worker_thread_| is set by SetUp(). I now use
an event to wait until |worker_thread_| is set.

+      }
+
       // Without synchronization, OnMainEntry() could be called twice without
       // generating an error.
       AutoSchedulerLock auto_lock(outer_->lock_);
       EXPECT_FALSE(outer_->main_entry_called_.IsSignaled());
       outer_->main_entry_called_.Signal();
     }
 
     scoped_refptr<Sequence> GetWork(
         SchedulerWorkerThread* worker_thread) override {
       EXPECT_EQ(outer_->worker_thread_.get(), worker_thread);
@@ skipping 88 matching lines @@
 
   // Sequences created by GetWork().
   std::vector<scoped_refptr<Sequence>> created_sequences_;
 
   // Sequences passed to EnqueueSequence().
   std::vector<scoped_refptr<Sequence>> re_enqueued_sequences_;
 
   // Number of times that RunTaskCallback() has been called.
   size_t num_run_tasks_ = 0;
 
+  // Synchronizes access to |main_entry_worker_thread_|.
+  SchedulerLock main_entry_worker_thread_lock_;
+
+  // The worker thread argument passed to OnMainEntry().
+  SchedulerWorkerThread* main_entry_worker_thread_ = nullptr;
+
   DISALLOW_COPY_AND_ASSIGN(TaskSchedulerWorkerThreadTest);
 };
 
 // Verify that when GetWork() continuously returns Sequences, all Tasks in these
 // Sequences run successfully. The test wakes up the SchedulerWorkerThread once.
 TEST_P(TaskSchedulerWorkerThreadTest, ContinuousWork) {
   // Set GetWork() to return |kNumSequencesPerTest| Sequences before starting to
   // return nullptr.
   SetNumSequencesToCreate(kNumSequencesPerTest);
 
@@ skipping 54 matching lines @@
 INSTANTIATE_TEST_CASE_P(OneTaskPerSequence,
                         TaskSchedulerWorkerThreadTest,
                         ::testing::Values(1));
 INSTANTIATE_TEST_CASE_P(TwoTasksPerSequence,
                         TaskSchedulerWorkerThreadTest,
                         ::testing::Values(2));
 
 }  // namespace
 }  // namespace internal
 }  // namespace base