Allow unit tests to use a mock audio input controller.

media/audio/test_audio_input_controller_factory.h

+// Copyright (c) 2009 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 MEDIA_AUDIO_TEST_AUDIO_INPUT_CONTROLLER_FACTORY_H_
+#define MEDIA_AUDIO_TEST_AUDIO_INPUT_CONTROLLER_FACTORY_H_
+#pragma once
+
+#include "media/audio/audio_input_controller.h"
+
+namespace media {
+
+class TestAudioInputControllerFactory;
+
+// TestAudioInputController and TestAudioInputControllerFactory are used for
+// testing consumers of AudioInputController. TestAudioInputControllerFactory
+// is a AudioInputController::Factory that creates TestAudioInputControllers.
+//
+// TestAudioInputController::Record and Close are overriden to do nothing. It is
+// expected that you'll grab the EventHandler from the TestAudioInputController
+// and invoke the callback methods when appropriate. In this way it's easy to
+// mock a AudioInputController.
+//
+// Typical usage:
+//   // Create and register factory.
+//   TestAudioInputControllerFactory factory;
+//   AudioInputController::set_factory(&factory);
+//
+//   // Do something that triggers creation of an AudioInputController.
+//   TestAudioInputController* controller = factory.last_controller();
+//   DCHECK(controller);
+//
+//   // Notify event handler with whatever data you want.
+//   controller->event_handler()->OnCreated(...);
+//
+//   // Do something that triggers AudioInputController::Record to be called.
+//   controller->event_handler()->OnData(...);
+//   controller->event_handler()->OnError(...);
+//
+//   // Make sure consumer of AudioInputController does the right thing.
+//   ...
+//   // Reset factory.
+//   AudioInputController::set_factory(NULL);
+
+class TestAudioInputController : public AudioInputController {
+ public:
+  TestAudioInputController(TestAudioInputControllerFactory* factory,
+                           EventHandler* event_handler);
+  virtual ~TestAudioInputController();
+
+  // Returns the event handler installed on the AudioInputController.
+  EventHandler* event_handler() const { return event_handler_; }
+
+  // Overriden to do nothing. It is assumed the caller will notify the event
+  // handler with recorded data and other events.
+  virtual void Record() {}
+  virtual void Close() {}
+
+ private:
+  // These are not owned by us and expected to be valid for this object's
+  // lifetime.
+  TestAudioInputControllerFactory* factory_;
+  EventHandler* event_handler_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestAudioInputController);
+};
+
+// Simple AudioInputController::Factory method that creates
+// TestAudioInputControllers.
+class TestAudioInputControllerFactory : public AudioInputController::Factory {
+ public:
+  TestAudioInputControllerFactory();
+
+  // AudioInputController::Factory methods.
+  AudioInputController* Create(
+      AudioInputController::EventHandler* event_handler,
+      AudioManager::Format format,
+      int channels,
+      int sample_rate,
+      int bits_per_sample,
+      int samples_per_packet);
+
+  TestAudioInputController* controller() const { return controller_; }
+
+ private:
+  friend class TestAudioInputController;
+
+  // Invoked by a TestAudioInputController when it gets destroyed.
+  void OnTestAudioInputControllerDestroyed(
+      TestAudioInputController* controller);
+
+  // The caller of Create owns this object.
+  TestAudioInputController* controller_;
+
+  DISALLOW_COPY_AND_ASSIGN(TestAudioInputControllerFactory);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_AUDIO_TEST_AUDIO_INPUT_CONTROLLER_FACTORY_H_