Reland Chrome power profiler service

content/browser/power_profiler/power_profiler_service_unittest.cc

+// Copyright 2014 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/message_loop/message_loop.h"
+#include "base/run_loop.h"
+#include "content/browser/browser_thread_impl.h"
+#include "content/browser/power_profiler/power_profiler_service.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace content {
+
+namespace {
+
+const int kNumEvents = 3;
+
+// Provide a set number of power events.
+class TestPowerDataProvider : public PowerDataProvider {
+ public:
+  TestPowerDataProvider(int count) : num_events_to_send_(count) {}
+  virtual ~TestPowerDataProvider() {}
+
+  virtual PowerEventVector GetData() OVERRIDE {
+    PowerEventVector events;
+    if (num_events_to_send_ == 0)
+      return events;
+
+    PowerEvent event;
+    event.type = PowerEvent::SOC_PACKAGE;
+    event.time = base::TimeTicks::Now();
+    event.value = 1.0;
+    events.push_back(event);
+
+    num_events_to_send_--;
+    return events;
+  }
+
+ private:
+  int num_events_to_send_;
+  DISALLOW_COPY_AND_ASSIGN(TestPowerDataProvider);
+};
+
+class TestPowerProfilerObserver : public PowerProfilerObserver {
+ public:
+  TestPowerProfilerObserver()
+      : valid_event_count_(0),
+        total_num_events_received_(0) {}
+  virtual ~TestPowerProfilerObserver() {}
+
+  virtual void OnPowerEvent(const PowerEventVector& events) OVERRIDE {
+    if (IsValidEvent(events[0]))
+      ++valid_event_count_;
+
+    total_num_events_received_++;
+    if (total_num_events_received_ >= kNumEvents) {
+      // All expected events received, exiting.
+      quit_closure_.Run();
+    }
+  }
+
+  int valid_event_count() const { return valid_event_count_; }
+  void set_quit_closure(base::Closure closure) { quit_closure_ = closure; }
+
+ private:
+  bool IsValidEvent(const PowerEvent& event) {
+    return event.type == PowerEvent::SOC_PACKAGE &&
+           !event.time.is_null() &&
+           event.value > 0;
+  }
+
+  int valid_event_count_;
+  int total_num_events_received_;
+  base::Closure quit_closure_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestPowerProfilerObserver);
+};
+
+} // namespace
+
+class PowerProfilerServiceTest : public testing::Test {
+ public:
+  void ServiceStartTest() {
+    service_.reset(new PowerProfilerService(
+        make_scoped_ptr<PowerDataProvider>(
+            new TestPowerDataProvider(kNumEvents)),
+        message_loop_.message_loop_proxy(),
+        base::TimeDelta::FromMilliseconds(1)));
+    EXPECT_TRUE(service_->IsAvailable());
+  }
+
+  void AddObserverTest() {
+    service_->AddObserver(&observer_);
+
+    // No PowerEvents received.
+    EXPECT_EQ(observer_.valid_event_count(), 0);
+  }
+
+  void RemoveObserverTest() {
+     service_->RemoveObserver(&observer_);
+
+    // Received |kNumEvents| events.
+    EXPECT_EQ(observer_.valid_event_count(), kNumEvents);
+  }
+
+ protected:
+  PowerProfilerServiceTest() : ui_thread_(BrowserThread::UI, &message_loop_) {}
+  virtual ~PowerProfilerServiceTest() {}
+
+  void RegisterQuitClosure(base::Closure closure) {
+    observer_.set_quit_closure(closure);
+  }
+
+ private:
+  scoped_ptr<PowerProfilerService> service_;
+  TestPowerProfilerObserver observer_;
+
+  // UI thread.
+  base::MessageLoopForUI message_loop_;
+  BrowserThreadImpl ui_thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(PowerProfilerServiceTest);
+};
+
+// Test whether PowerProfilerService dispatches power events to observer
+// properly.
+TEST_F(PowerProfilerServiceTest, AvailableService) {
+  base::RunLoop run_loop;
+  RegisterQuitClosure(run_loop.QuitClosure());
+
+  ServiceStartTest();
+  AddObserverTest();
+
+  run_loop.Run();
+
+  RemoveObserverTest();
+}
+
+}  // namespace content