Add a PeerConnection integration test for adding an audio track mid-call

webrtc/pc/peerconnection_integrationtest.cc

 /*
  *  Copyright 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 1375 matching lines @@
 
 // This test sets up a audio call initially, with the callee rejecting video
 // initially. Then later the callee decides to upgrade to audio/video, and
 // initiates a new offer/answer exchange.
 TEST_F(PeerConnectionIntegrationTest, AudioToVideoUpgrade) {
   ASSERT_TRUE(CreatePeerConnectionWrappers());
   ConnectFakeSignaling();
   // Initially, offer an audio/video stream from the caller, but refuse to
   // send/receive video on the callee side.
   caller()->AddAudioVideoMediaStream();
-  callee()->AddMediaStreamFromTracks(callee()->CreateLocalAudioTrack(),
-                                     nullptr);
+  callee()->AddAudioOnlyMediaStream();
   PeerConnectionInterface::RTCOfferAnswerOptions options;
   options.offer_to_receive_video = 0;
   callee()->SetOfferAnswerOptions(options);
   // Do offer/answer and make sure audio is still received end-to-end.
   caller()->CreateAndSetAndSignalOffer();
   ASSERT_TRUE_WAIT(SignalingStateStable(), kDefaultTimeout);
   ExpectNewFramesReceivedWithWait(kDefaultExpectedAudioFrameCount, 0,
                                   kDefaultExpectedAudioFrameCount, 0,
                                   kMaxWaitForFramesMs);
   // Sanity check that the callee's description has a rejected video section.
@@ skipping 10 matching lines @@
   callee()->SetOfferAnswerOptions(options);
   callee()->CreateAndSetAndSignalOffer();
   ASSERT_TRUE_WAIT(SignalingStateStable(), kDefaultTimeout);
   // Expect additional audio frames to be received after the upgrade.
   ExpectNewFramesReceivedWithWait(
       kDefaultExpectedAudioFrameCount, kDefaultExpectedVideoFrameCount,
       kDefaultExpectedAudioFrameCount, kDefaultExpectedVideoFrameCount,
       kMaxWaitForFramesMs);
 }
 
+// Simpler than the above test; just add an audio track to an established
+// video-only connection.
+TEST_F(PeerConnectionIntegrationTest, AddAudioToVideoOnlyCall) {
+  ASSERT_TRUE(CreatePeerConnectionWrappers());
+  ConnectFakeSignaling();
+  // Do initial offer/answer with just a video track.
+  caller()->AddVideoOnlyMediaStream();
+  callee()->AddVideoOnlyMediaStream();
+  caller()->CreateAndSetAndSignalOffer();
+  ASSERT_TRUE_WAIT(SignalingStateStable(), kDefaultTimeout);
+  // Now add an audio track and do another offer/answer.
+  caller()->AddMediaStreamFromTracksWithLabel(caller()->CreateLocalAudioTrack(),
+                                              nullptr, "audio_stream");
+  callee()->AddMediaStreamFromTracksWithLabel(callee()->CreateLocalAudioTrack(),
+                                              nullptr, "audio_stream");
+  caller()->CreateAndSetAndSignalOffer();
+  ASSERT_TRUE_WAIT(SignalingStateStable(), kDefaultTimeout);
+  // Ensure both audio and video frames are received end-to-end.
+  ExpectNewFramesReceivedWithWait(
+      kDefaultExpectedAudioFrameCount, kDefaultExpectedVideoFrameCount,
+      kDefaultExpectedAudioFrameCount, kDefaultExpectedVideoFrameCount,
+      kMaxWaitForFramesMs);
+}
+
 // This test sets up a call that's transferred to a new caller with a different
 // DTLS fingerprint.
 TEST_F(PeerConnectionIntegrationTest, CallTransferredForCallee) {
   ASSERT_TRUE(CreatePeerConnectionWrappers());
   ConnectFakeSignaling();
   caller()->AddAudioVideoMediaStream();
   callee()->AddAudioVideoMediaStream();
   caller()->CreateAndSetAndSignalOffer();
   ASSERT_TRUE_WAIT(SignalingStateStable(), kDefaultTimeout);
 
@@ skipping 1532 matching lines @@
   caller()->CreateAndSetAndSignalOffer();
   ASSERT_TRUE_WAIT(SignalingStateStable(), kDefaultTimeout);
   // Wait for additional audio frames to be received by the callee.
   ExpectNewFramesReceivedWithWait(0, 0, kDefaultExpectedAudioFrameCount, 0,
                                   kMaxWaitForFramesMs);
 }
 
 }  // namespace
 
 #endif  // if !defined(THREAD_SANITIZER)