Unit tests for AudioRendererHost...

chrome/browser/renderer_host/audio_renderer_host_unittest.cc

Index: chrome/browser/renderer_host/audio_renderer_host_unittest.cc
===================================================================
--- chrome/browser/renderer_host/audio_renderer_host_unittest.cc	(revision 20328)
+++ chrome/browser/renderer_host/audio_renderer_host_unittest.cc	(working copy)
@@ -4,16 +4,121 @@
 
 #include "base/message_loop.h"
 #include "base/process.h"
+#include "base/process_util.h"
 #include "base/scoped_ptr.h"
 #include "chrome/browser/renderer_host/audio_renderer_host.h"
+#include "chrome/common/render_messages.h"
+#include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::InSequence;
+using ::testing::Return;
+using ::testing::SetArgumentPointee;
+
+namespace {
+
+const int kInvalidId = -1;
+const int kProcessId = 100;
+const int kRouteId = 200;
+const int kBufferCapacity = 65536;
+const int kPacketSize = 16384;
+
+}  // namespace
+
+class MockAudioRendererHost : public AudioRendererHost {
+ public:
+  MockAudioRendererHost(MessageLoop* loop)
+      : AudioRendererHost(loop) {
+  }
+
+  // A list of mock methods.
+  MOCK_METHOD4(OnRequestPacket,
+               void(int routing_id, int stream_id,
+                    size_t bytes_in_buffer, int64 message_timestamp));
+
+  MOCK_METHOD3(OnStreamCreated,
+               void(int routing_id, int stream_id, int length));
+
+  MOCK_METHOD4(OnStreamStateChanged,
+               void(int routing_id, int stream_id,
+                    AudioOutputStream::State state, int info));
+
+  MOCK_METHOD4(OnStreamVolume,
+               void(int routing_id, int stream_id, double left, double right));
+
+  base::SharedMemory* shared_memory() { return shared_memory_.get(); }
+
+ protected:
+  // This method is used to dispatch IPC messages to the renderer. We intercept
+  // these messages here and dispatch to our mock methods to verify the
+  // conversation between this object and the renderer.
+  virtual void Send(IPC::Message* message) {
+    CHECK(message);
+
+    // In this method we dispatch the messages to the according handlers as if
+    // we are the renderer.
+    bool handled = true;
+    IPC_BEGIN_MESSAGE_MAP(MockAudioRendererHost, *message)
+      IPC_MESSAGE_HANDLER(ViewMsg_RequestAudioPacket, OnRequestPacket)
+      IPC_MESSAGE_HANDLER(ViewMsg_NotifyAudioStreamCreated, OnStreamCreated)
+      IPC_MESSAGE_HANDLER(ViewMsg_NotifyAudioStreamStateChanged,
+                          OnStreamStateChanged)
+      IPC_MESSAGE_HANDLER(ViewMsg_NotifyAudioStreamVolume, OnStreamVolume)
+      IPC_MESSAGE_UNHANDLED(handled = false)
+    IPC_END_MESSAGE_MAP()
+    EXPECT_TRUE(handled);
+
+    delete message;
+  }
+
+ private:
+  // These handler methods do minimal things and delegate to the mock methods.
+  void OnRequestPacket(const IPC::Message& msg, int stream_id,
+                       size_t bytes_in_buffer, int64 message_timestamp) {
+    OnRequestPacket(msg.routing_id(), stream_id, bytes_in_buffer,
+                    message_timestamp);
+  }
+
+  void OnStreamCreated(const IPC::Message& msg, int stream_id,
+                       base::SharedMemoryHandle handle, int length) {
+    // Maps the shared memory.
+    shared_memory_.reset(new base::SharedMemory(handle, true));
+    CHECK(shared_memory_->Map(length));
+    CHECK(shared_memory_->memory());
+
+    // And then delegate the call to the mock method.
+    OnStreamCreated(msg.routing_id(), stream_id, length);
+  }
+
+  void OnStreamStateChanged(const IPC::Message& msg, int stream_id,
+                            AudioOutputStream::State state, int info) {
+    OnStreamStateChanged(msg.routing_id(), stream_id, state, info);
+  }
+
+  void OnStreamVolume(const IPC::Message& msg, int stream_id,
+                      double left, double right) {
+    OnStreamVolume(msg.routing_id(), stream_id, left, right);
+  }
+
+  scoped_ptr<base::SharedMemory> shared_memory_;
+
+  DISALLOW_COPY_AND_ASSIGN(MockAudioRendererHost);
+};
+
 class AudioRendererHostTest : public testing::Test {
+ public:
+  AudioRendererHostTest()
+      : current_stream_id_(0) {
+  }
+
  protected:
   virtual void SetUp() {
     // Create a message loop so AudioRendererHost can use it.
     message_loop_.reset(new MessageLoop(MessageLoop::TYPE_IO));
-    host_ = new AudioRendererHost(message_loop_.get());
+    host_ = new MockAudioRendererHost(message_loop_.get());
+    CHECK(host_);
   }
 
   virtual void TearDown() {
@@ -24,10 +129,83 @@
     message_loop_->RunAllPending();
   }
 
-  scoped_refptr<AudioRendererHost> host_;
+  AudioRendererHost::IPCAudioSource* CreateAudioStream(
+      AudioManager::Format format) {
+    InSequence s;
+
+    // 1. We will first receive a OnStreamCreated() signal.
+    EXPECT_CALL(*host_,
+                OnStreamCreated(kRouteId, current_stream_id_, kPacketSize));
+
+    // 2. First packet request will arrive. This request is sent by
+    //    IPCAudioSource::CreateIPCAudioSource to start buffering.
+    EXPECT_CALL(*host_, OnRequestPacket(kRouteId, current_stream_id_, 0, _));
+
+    AudioRendererHost::IPCAudioSource* source =
+        AudioRendererHost::IPCAudioSource::CreateIPCAudioSource(
+            host_,
+            kProcessId,
+            kRouteId,
+            current_stream_id_,
+            base::GetCurrentProcessHandle(),
+            format,
+            2,
+            AudioManager::kAudioCDSampleRate,
+            16,
+            kPacketSize,
+            kBufferCapacity);
+    EXPECT_TRUE(source);
+    EXPECT_EQ(kProcessId, source->process_id());
+    EXPECT_EQ(kRouteId, source->route_id());
+    EXPECT_EQ(current_stream_id_, source->stream_id());
+    return source;
+  }
+
+  AudioRendererHost::IPCAudioSource* CreateRealStream() {
+    return CreateAudioStream(AudioManager::AUDIO_PCM_LINEAR);
+  }
+
+  AudioRendererHost::IPCAudioSource* CreateMockStream() {
+    return CreateAudioStream(AudioManager::AUDIO_MOCK);
+  }
+
+  int current_stream_id_;
+  scoped_refptr<MockAudioRendererHost> host_;
   scoped_ptr<MessageLoop> message_loop_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(AudioRendererHostTest);
 };
 
-TEST_F(AudioRendererHostTest, NoTest) {
-  // TODO(hclam): come up with useful tests.
+// Audio output stream only works stably on windows. Also there's no mock
+// audio output streams for mac and linux.
+// TODO(hclam): make these tests work on mac and linux.
+#if defined(OS_WIN)
+
+TEST_F(AudioRendererHostTest, CreateMockStream) {
+  scoped_ptr<AudioRendererHost::IPCAudioSource> source(CreateMockStream());
 }
+
+TEST_F(AudioRendererHostTest, MockStreamDataConversation) {
+  scoped_ptr<AudioRendererHost::IPCAudioSource> source(CreateMockStream());
+
+  // We will receive packet requests until the buffer is full. We first send
+  // three packets of 16KB, then we send packets of 1KB until the buffer is
+  // full. Then there will no more packet requests.
+  EXPECT_CALL(*host_,
+      OnRequestPacket(kRouteId, current_stream_id_, kPacketSize, _));
+  EXPECT_CALL(*host_,
+      OnRequestPacket(kRouteId, current_stream_id_, 2 * kPacketSize, _));
+  for (int size = 3 * kPacketSize; size < kBufferCapacity; size += 1024) {
+    EXPECT_CALL(*host_, OnRequestPacket(kRouteId, current_stream_id_, size, _));
+  }
+
+  source->NotifyPacketReady(kPacketSize);
+  source->NotifyPacketReady(kPacketSize);
+  source->NotifyPacketReady(kPacketSize);
+  for (int size = 0; size < kPacketSize; size += 1024) {
+    source->NotifyPacketReady(1024);
+  }
+}
+
+#endif