Revert of Revert of Add a WorkerScheduler and a WebThreadImplForWorker

content/child/scheduler/webthread_impl_for_worker_scheduler_unittest.cc

Index: content/child/scheduler/webthread_impl_for_worker_scheduler_unittest.cc
diff --git a/content/child/scheduler/webthread_impl_for_worker_scheduler_unittest.cc b/content/child/scheduler/webthread_impl_for_worker_scheduler_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b03749a620889fa3aee22c64e41726ff6e3f6cba
--- /dev/null
+++ b/content/child/scheduler/webthread_impl_for_worker_scheduler_unittest.cc
@@ -0,0 +1,170 @@
+// Copyright 2015 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 "content/child/scheduler/webthread_impl_for_worker_scheduler.h"
+
+#include "base/synchronization/waitable_event.h"
+#include "content/child/scheduler/worker_scheduler_impl.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/WebKit/public/platform/WebTraceLocation.h"
+
+using testing::_;
+using testing::AnyOf;
+using testing::ElementsAre;
+using testing::Invoke;
+
+namespace content {
+namespace {
+
+class NopTask : public blink::WebThread::Task {
+ public:
+  ~NopTask() override {}
+
+  void run() {}
+};
+
+class MockTask : public blink::WebThread::Task {
+ public:
+  ~MockTask() override {}
+
+  MOCK_METHOD0(run, void());
+};
+
+class MockIdleTask : public blink::WebThread::IdleTask {
+ public:
+  ~MockIdleTask() override {}
+
+  MOCK_METHOD1(run, void(double deadline));
+};
+
+class TestObserver : public blink::WebThread::TaskObserver {
+ public:
+  explicit TestObserver(std::string* calls) : calls_(calls) {}
+
+  ~TestObserver() override {}
+
+  void willProcessTask() override { calls_->append(" willProcessTask"); }
+
+  void didProcessTask() override { calls_->append(" didProcessTask"); }
+
+ private:
+  std::string* calls_;  // NOT OWNED
+};
+
+class TestTask : public blink::WebThread::Task {
+ public:
+  explicit TestTask(std::string* calls) : calls_(calls) {}
+
+  ~TestTask() override {}
+
+  void run() override { calls_->append(" run"); }
+
+ private:
+  std::string* calls_;  // NOT OWNED
+};
+
+void addTaskObserver(WebThreadImplForWorkerScheduler* thread,
+                     TestObserver* observer) {
+  thread->addTaskObserver(observer);
+}
+
+void removeTaskObserver(WebThreadImplForWorkerScheduler* thread,
+                        TestObserver* observer) {
+  thread->removeTaskObserver(observer);
+}
+
+}  // namespace
+
+class WebThreadImplForWorkerSchedulerTest : public testing::Test {
+ public:
+  WebThreadImplForWorkerSchedulerTest() {}
+
+  ~WebThreadImplForWorkerSchedulerTest() override {}
+
+  void SetUp() override {
+    thread_.reset(new WebThreadImplForWorkerScheduler("test thread"));
+  }
+
+  void RunOnWorkerThread(const tracked_objects::Location& from_here,
+                         const base::Closure& task) {
+    base::WaitableEvent completion(false, false);
+    thread_->TaskRunner()->PostTask(
+        from_here,
+        base::Bind(&WebThreadImplForWorkerSchedulerTest::RunOnWorkerThreadTask,
+                   base::Unretained(this), task, &completion));
+    completion.Wait();
+  }
+
+ protected:
+  void RunOnWorkerThreadTask(const base::Closure& task,
+                             base::WaitableEvent* completion) {
+    task.Run();
+    completion->Signal();
+  }
+
+  scoped_ptr<WebThreadImplForWorkerScheduler> thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebThreadImplForWorkerSchedulerTest);
+};
+
+TEST_F(WebThreadImplForWorkerSchedulerTest, TestDefaultTask) {
+  scoped_ptr<MockTask> task(new MockTask());
+  base::WaitableEvent completion(false, false);
+
+  EXPECT_CALL(*task, run());
+  ON_CALL(*task, run())
+      .WillByDefault(Invoke([&completion]() { completion.Signal(); }));
+
+  thread_->postTask(blink::WebTraceLocation(), task.release());
+  completion.Wait();
+}
+
+TEST_F(WebThreadImplForWorkerSchedulerTest,
+       TestTaskExecutedBeforeThreadDeletion) {
+  scoped_ptr<MockTask> task(new MockTask());
+  base::WaitableEvent completion(false, false);
+
+  EXPECT_CALL(*task, run());
+  ON_CALL(*task, run())
+      .WillByDefault(Invoke([&completion]() { completion.Signal(); }));
+
+  thread_->postTask(blink::WebTraceLocation(), task.release());
+  thread_.reset();
+}
+
+TEST_F(WebThreadImplForWorkerSchedulerTest, TestIdleTask) {
+  scoped_ptr<MockIdleTask> task(new MockIdleTask());
+  base::WaitableEvent completion(false, false);
+
+  EXPECT_CALL(*task, run(_));
+  ON_CALL(*task, run(_))
+      .WillByDefault(Invoke([&completion](double) { completion.Signal(); }));
+
+  thread_->postIdleTask(blink::WebTraceLocation(), task.release());
+  // We need to post a wakeup task or idle work will never happen.
+  thread_->postDelayedTask(blink::WebTraceLocation(), new NopTask(), 50ul);
+
+  completion.Wait();
+}
+
+TEST_F(WebThreadImplForWorkerSchedulerTest, TestTaskObserver) {
+  std::string calls;
+  TestObserver observer(&calls);
+
+  RunOnWorkerThread(FROM_HERE,
+                    base::Bind(&addTaskObserver, thread_.get(), &observer));
+  thread_->postTask(blink::WebTraceLocation(), new TestTask(&calls));
+  RunOnWorkerThread(FROM_HERE,
+                    base::Bind(&removeTaskObserver, thread_.get(), &observer));
+
+  // We need to be careful what we test here.  We want to make sure the
+  // observers are un in the expected order before and after the task.
+  // Sometimes we get an internal scheduler task running before or after
+  // TestTask as well. This is not a bug, and we need to make sure the test
+  // doesn't fail when that happens.
+  EXPECT_THAT(calls, testing::HasSubstr("willProcessTask run didProcessTask"));
+}
+
+}  // namespace content