Forward the SignalFirstPacketReceived to RtpReceiver.

webrtc/api/peerconnection_unittest.cc

Index: webrtc/api/peerconnection_unittest.cc
diff --git a/webrtc/api/peerconnection_unittest.cc b/webrtc/api/peerconnection_unittest.cc
index 24411ab729060c09c9658aab987b49e0b9db85f5..4d9bf8f8bd3e88af38712c44a376909ac7ce58c9 100644
--- a/webrtc/api/peerconnection_unittest.cc
+++ b/webrtc/api/peerconnection_unittest.cc
@@ -146,6 +146,37 @@ class SignalingMessageReceiver {
   virtual ~SignalingMessageReceiver() {}
 };
 
+class MockRtpReceiverObserver : public webrtc::RtpReceiverObserverInterface {
+ public:
+  MockRtpReceiverObserver()

[pthatcher1, 2016/06/08 17:35:55]

I'd suggest just passing the kind (or expected cricket::MediaType; see below)
into the constructor.

+      : is_first_audio_packet_recevied_(false),
+        is_first_video_packet_recevied_(false),
+        kind_("unset") {}
+
+  void OnFirstPacketReceived(cricket::MediaType media_type) override {
+    if (media_type == cricket::MEDIA_TYPE_AUDIO) {
+      is_first_audio_packet_recevied_ = true;
+    } else if (media_type == cricket::MEDIA_TYPE_VIDEO) {
+      is_first_video_packet_recevied_ = true;
+    }

[pthatcher1, 2016/06/08 17:35:55]

Given the unlikelyhood of getting the wrong media type, an
ASSERT_EQ(expected_media_type_, media_type) here might make more sense.  Then
you just have store "first_packet_received_ = true" here and the checking code
will be much more simple.

+  }
+
+  void SetKind(std::string kind) { kind_ = kind; }
+
+  std::string kind() { return kind_; }
+
+  bool IsFirstAudioPacketReceived() { return is_first_audio_packet_recevied_; }

[pthatcher1, 2016/06/08 17:35:55]

Using lowercase first_x_packet_received() is probably a better fit.  The "Is"
prefix sounds awkward, and the simple reading of a member variable matches the
lowercase style more.

+
+  bool IsFirstVideoPacketReceived() { return is_first_video_packet_recevied_; }
+
+  virtual ~MockRtpReceiverObserver() {}
+
+ private:
+  bool is_first_audio_packet_recevied_;
+  bool is_first_video_packet_recevied_;

[pthatcher1, 2016/06/08 17:35:55]

You can use "= false" here and avoid needing to set it in the constructor.

[pthatcher1, 2016/06/08 17:35:55]

Just "first_x_packet_received_" would be enough.  The "is_" sounds awkward.

+  std::string kind_;

[pthatcher1, 2016/06/08 17:35:55]

I think it might make more sense to store the expected_media_type_ here, going
along with the comment above about using an ASSERT_EQ.

+};
+
 class PeerConnectionTestClient : public webrtc::PeerConnectionObserver,
                                  public SignalingMessageReceiver,
                                  public ObserverInterface {
@@ -777,6 +808,11 @@ class PeerConnectionTestClient : public webrtc::PeerConnectionObserver,
     return pc()->ice_gathering_state();
   }
 
+  std::vector<std::unique_ptr<MockRtpReceiverObserver>> const&
+  rtp_receiver_observers() {
+    return rtp_receiver_observers_;
+  }
+
  private:
   class DummyDtmfObserver : public DtmfSenderObserverInterface {
    public:
@@ -867,6 +903,8 @@ class PeerConnectionTestClient : public webrtc::PeerConnectionObserver,
     std::unique_ptr<SessionDescriptionInterface> desc(
         webrtc::CreateSessionDescription("offer", msg, nullptr));
     EXPECT_TRUE(DoSetRemoteDescription(desc.release()));
+    // Register the RtpReceiverObserver after receivers are created.
+    SetRtpReceiverObservers();
     std::unique_ptr<SessionDescriptionInterface> answer;
     EXPECT_TRUE(DoCreateAnswer(&answer));
     std::string sdp;
@@ -883,6 +921,8 @@ class PeerConnectionTestClient : public webrtc::PeerConnectionObserver,
     std::unique_ptr<SessionDescriptionInterface> desc(
         webrtc::CreateSessionDescription("answer", msg, nullptr));
     EXPECT_TRUE(DoSetRemoteDescription(desc.release()));
+    // Register the RtpReceiverObserver after receivers are created.
+    SetRtpReceiverObservers();
   }
 
   bool DoCreateOfferAnswer(std::unique_ptr<SessionDescriptionInterface>* desc,
@@ -940,6 +980,16 @@ class PeerConnectionTestClient : public webrtc::PeerConnectionObserver,
     return true;
   }
 
+  void SetRtpReceiverObservers() {
+    for (auto receiver : pc()->GetReceivers()) {
+      std::unique_ptr<MockRtpReceiverObserver> observer(
+          new MockRtpReceiverObserver());
+      observer->SetKind(receiver->track()->kind());
+      receiver->SetObserver(observer.get());
+      rtp_receiver_observers_.push_back(std::move(observer));
+    }
+  }
+
   bool DoSetRemoteDescription(SessionDescriptionInterface* desc) {
     rtc::scoped_refptr<MockSetSessionDescriptionObserver>
         observer(new rtc::RefCountedObject<
@@ -1023,6 +1073,8 @@ class PeerConnectionTestClient : public webrtc::PeerConnectionObserver,
 
   rtc::scoped_refptr<DataChannelInterface> data_channel_;
   std::unique_ptr<MockDataChannelObserver> data_observer_;
+
+  std::vector<std::unique_ptr<MockRtpReceiverObserver>> rtp_receiver_observers_;
 };
 
 class P2PTestConductor : public testing::Test {
@@ -1312,6 +1364,23 @@ class P2PTestConductor : public testing::Test {
     return old;
   }
 
+  void CheckRtpReceiverObserverAreCalled(PeerConnectionTestClient* client) {
+    for (auto const& observer : client->rtp_receiver_observers()) {
+      if (observer->kind() == webrtc::MediaStreamTrackInterface::kAudioKind) {
+        EXPECT_TRUE_WAIT(observer->IsFirstAudioPacketReceived(),
+                         kMaxWaitForFramesMs);
+        EXPECT_FALSE(observer->IsFirstVideoPacketReceived());
+      } else if (observer->kind() ==
+                 webrtc::MediaStreamTrackInterface::kVideoKind) {
+        EXPECT_FALSE(observer->IsFirstAudioPacketReceived());
+        EXPECT_TRUE_WAIT(observer->IsFirstVideoPacketReceived(),
+                         kMaxWaitForFramesMs);
+      } else {
+        EXPECT_TRUE(false) << "Unknown RtpReceiver kind.";
+      }

[pthatcher1, 2016/06/08 17:35:55]

With my other suggestion about ASSERT_EQ(media_type, ....), this could just be:

EXPECT_TRUE_WAIT(observer->first_packet_received(), kMaxWaitForFrameMs);

[Zhi Huang, 2016/06/09 00:37:36]

This make the code much cleaner.

+    }
+  }
+
  private:
   // |worker_thread_| is used by both |initiating_client_| and
   // |receiving_client_|. Must be destroyed last.
@@ -1329,6 +1398,13 @@ class P2PTestConductor : public testing::Test {
 // https://code.google.com/p/webrtc/issues/detail?id=1205 for details.
 #if !defined(THREAD_SANITIZER)
 
+TEST_F(P2PTestConductor, TestRtpReceiverObserverCallbackFunction) {
+  ASSERT_TRUE(CreateTestClients());
+  LocalP2PTest();
+  CheckRtpReceiverObserverAreCalled(initializing_client());
+  CheckRtpReceiverObserverAreCalled(receiving_client());
+}
+
 // This test sets up a Jsep call between two parties and test Dtmf.
 // TODO(holmer): Disabled due to sometimes crashing on buildbots.
 // See issue webrtc/2378.