Fix the volume controlling behaviors.

chrome/browser/ui/views/ash/volume_controller_chromeos_browsertest.cc

+// 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.
+
+#include "chrome/browser/ui/views/ash/volume_controller_chromeos.h"
+
+#include "chrome/browser/chromeos/audio/audio_handler.h"
+#include "chrome/browser/chromeos/audio/audio_mixer.h"
+#include "chrome/test/base/in_process_browser_test.h"
+#include "chrome/test/base/ui_test_utils.h"
+#include "ui/base/accelerators/accelerator.h"
+
+namespace {
+
+class MockAudioMixer : public chromeos::AudioMixer {
+ public:
+  MockAudioMixer()
+      : volume_(0.0),
+        is_muted_(false) {
+  }
+
+  virtual void Init() OVERRIDE {
+  }
+
+  virtual double GetVolumePercent() OVERRIDE {
+    return volume_;
+  }
+
+  virtual void SetVolumePercent(double percent) OVERRIDE {
+    volume_ = percent;
+  }
+
+  virtual bool IsMuted() OVERRIDE {
+    return is_muted_;
+  }
+
+  virtual void SetMuted(bool do_mute) OVERRIDE {
+    is_muted_ = do_mute;
+  }
+
+ private:
+  double volume_;
+  bool is_muted_;
+
+  DISALLOW_COPY_AND_ASSIGN(MockAudioMixer);
+};
+
+// This class has to be browsertest because AudioHandler uses prefs_service.
+class VolumeControllerTest : public InProcessBrowserTest {
+ public:
+  virtual void SetUpOnMainThread() OVERRIDE {
+    // First we should shutdown the default audio handler.
+    chromeos::AudioHandler::Shutdown();
+    audio_mixer_ = new MockAudioMixer;
+    chromeos::AudioHandler::InitializeForTesting(audio_mixer_);
+  }
+
+  virtual void CleanupOnMainThread() OVERRIDE {
+    chromeos::AudioHandler::Shutdown();
+    audio_mixer_ = NULL;
+  }
+
+ protected:
+  void VolumeMute() {
+    ui::Accelerator dummy;
+    volume_controller_.HandleVolumeMute(dummy);

[Daniel Erat, 2012/05/19 00:02:06]

nit: can you shorten this to:

  ...HandleVolumeMute(ui::Accelerator())

?

[Jun Mukai, 2012/05/19 00:18:32]

Done.

+  }
+
+  void VolumeUp() {
+    ui::Accelerator dummy;
+    volume_controller_.HandleVolumeUp(dummy);

[Daniel Erat, 2012/05/19 00:02:06]

same here

[Jun Mukai, 2012/05/19 00:18:32]

Done.

+  }
+
+  void VolumeDown() {
+    ui::Accelerator dummy;
+    volume_controller_.HandleVolumeDown(dummy);

[Daniel Erat, 2012/05/19 00:02:06]

and here

[Jun Mukai, 2012/05/19 00:18:32]

Done.

+  }
+
+  MockAudioMixer* audio_mixer() { return audio_mixer_; }
+
+private:
+  VolumeController volume_controller_;
+  MockAudioMixer* audio_mixer_;
+};
+
+IN_PROC_BROWSER_TEST_F(VolumeControllerTest, VolumeUpAndDown) {
+  double initial_volume = audio_mixer()->GetVolumePercent();

[Daniel Erat, 2012/05/19 00:02:06]

nit: call SetVolumePercent(50.0) at the beginning of this test?

[Jun Mukai, 2012/05/19 00:18:32]

Done.

+
+  VolumeUp();
+  EXPECT_LT(initial_volume, audio_mixer()->GetVolumePercent());
+  VolumeDown();
+  EXPECT_DOUBLE_EQ(initial_volume, audio_mixer()->GetVolumePercent());
+  VolumeDown();
+  EXPECT_GT(initial_volume, audio_mixer()->GetVolumePercent());
+}
+
+IN_PROC_BROWSER_TEST_F(VolumeControllerTest, VolumeDownToZero) {
+  // Setting to very small
+  audio_mixer()->SetVolumePercent(0.1);
+
+  VolumeDown();
+  EXPECT_DOUBLE_EQ(0.0, audio_mixer()->GetVolumePercent());
+  VolumeDown();
+  EXPECT_DOUBLE_EQ(0.0, audio_mixer()->GetVolumePercent());
+  VolumeUp();
+  EXPECT_LT(0.0, audio_mixer()->GetVolumePercent());
+}
+
+IN_PROC_BROWSER_TEST_F(VolumeControllerTest, VolumeUpTo100) {
+  // Setting to almost max
+  audio_mixer()->SetVolumePercent(99.0);
+
+  VolumeUp();
+  EXPECT_DOUBLE_EQ(100.0, audio_mixer()->GetVolumePercent());
+  VolumeUp();
+  EXPECT_DOUBLE_EQ(100.0, audio_mixer()->GetVolumePercent());
+  VolumeDown();
+  EXPECT_GT(100.0, audio_mixer()->GetVolumePercent());
+}
+
+IN_PROC_BROWSER_TEST_F(VolumeControllerTest, Mutes) {
+  EXPECT_FALSE(audio_mixer()->IsMuted());

[Daniel Erat, 2012/05/19 00:02:06]

nit: s/EXPECT_FALSE/ASSERT_FALSE/, since the rest of this test will be
irrelevant if the starting state is wrong

[Jun Mukai, 2012/05/19 00:18:32]

Done.

+  double initial_volume = audio_mixer()->GetVolumePercent();
+
+  VolumeMute();
+  EXPECT_TRUE(audio_mixer()->IsMuted());
+
+  // Further mute buttons doesn't make effects.

[Daniel Erat, 2012/05/19 00:02:06]

nit: s/make/have/

[Jun Mukai, 2012/05/19 00:18:32]

Done.

+  VolumeMute();
+  EXPECT_TRUE(audio_mixer()->IsMuted());
+
+  // Right after the volume up after set_mute recovers to original volume.
+  VolumeUp();
+  EXPECT_FALSE(audio_mixer()->IsMuted());
+  EXPECT_DOUBLE_EQ(initial_volume, audio_mixer()->GetVolumePercent());
+
+  VolumeMute();
+  // After the volume down, the volume goes down to zero explicitly.
+  VolumeDown();
+  EXPECT_TRUE(audio_mixer()->IsMuted());
+  EXPECT_DOUBLE_EQ(0.0, audio_mixer()->GetVolumePercent());
+
+  // Thus, further VolumeUp doesn't recover the volume, it's just slightly
+  // bigger than 0.
+  VolumeUp();
+  EXPECT_LT(0.0, audio_mixer()->GetVolumePercent());
+  EXPECT_GT(initial_volume, audio_mixer()->GetVolumePercent());
+}
+
+}  // namespace