TransportFeedback must be able to start with dropped packets.

webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy_unittest.cc

 /*
  *  Copyright (c) 2015 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.
  */
 
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 #include "webrtc/modules/pacing/packet_router.h"
 #include "webrtc/modules/remote_bitrate_estimator/remote_estimator_proxy.h"
 #include "webrtc/modules/rtp_rtcp/source/rtcp_packet/transport_feedback.h"
 #include "webrtc/system_wrappers/include/clock.h"
 
 using ::testing::_;
 using ::testing::InSequence;
 using ::testing::Invoke;
+using ::testing::Return;
 
 namespace webrtc {
 
 class MockPacketRouter : public PacketRouter {
  public:
   MOCK_METHOD1(SendFeedback, bool(rtcp::TransportFeedback* packet));
 };
 
 class RemoteEstimatorProxyTest : public ::testing::Test {
  public:
@@ skipping 68 matching lines @@
                   status_vec[0]);
         std::vector<int64_t> delta_vec = packet->GetReceiveDeltasUs();
         EXPECT_EQ(1u, delta_vec.size());
         EXPECT_EQ(kBaseTimeMs, (packet->GetBaseTimeUs() + delta_vec[0]) / 1000);
         return true;
       }));
 
   Process();
 }
 
+TEST_F(RemoteEstimatorProxyTest, FeedbackWithMissingStart) {
+  // First feedback.
+  IncomingPacket(kBaseSeq, kBaseTimeMs);
+  IncomingPacket(kBaseSeq + 1, kBaseTimeMs + 1000);
+  EXPECT_CALL(router_, SendFeedback(_)).Times(1).WillOnce(Return(true));
+  Process();
+
+  // Second feedback starts with a missing packet (DROP kBaseSeq + 2).
+  IncomingPacket(kBaseSeq + 3, kBaseTimeMs + 3000);
+
+  EXPECT_CALL(router_, SendFeedback(_))
+      .Times(1)
+      .WillOnce(Invoke([this](rtcp::TransportFeedback* packet) {
+        packet->Build();
+        EXPECT_EQ(kBaseSeq + 2, packet->GetBaseSequence());
+        EXPECT_EQ(kMediaSsrc, packet->GetMediaSourceSsrc());
+
+        std::vector<rtcp::TransportFeedback::StatusSymbol> status_vec =
+            packet->GetStatusVector();
+        EXPECT_EQ(2u, status_vec.size());
+        EXPECT_EQ(rtcp::TransportFeedback::StatusSymbol::kNotReceived,
+                  status_vec[0]);
+        EXPECT_EQ(rtcp::TransportFeedback::StatusSymbol::kReceivedSmallDelta,
+                  status_vec[1]);
+        std::vector<int64_t> delta_vec = packet->GetReceiveDeltasUs();
+        EXPECT_EQ(1u, delta_vec.size());
+        EXPECT_EQ(kBaseTimeMs + 3000,
+                  (packet->GetBaseTimeUs() + delta_vec[0]) / 1000);
+        return true;
+      }));
+
+  Process();
+}
+
 TEST_F(RemoteEstimatorProxyTest, SendsFeedbackWithVaryingDeltas) {
   IncomingPacket(kBaseSeq, kBaseTimeMs);
   IncomingPacket(kBaseSeq + 1, kBaseTimeMs + kMaxSmallDeltaMs);
   IncomingPacket(kBaseSeq + 2, kBaseTimeMs + (2 * kMaxSmallDeltaMs) + 1);
 
   EXPECT_CALL(router_, SendFeedback(_))
       .Times(1)
       .WillOnce(Invoke([this](rtcp::TransportFeedback* packet) {
         packet->Build();
         EXPECT_EQ(kBaseSeq, packet->GetBaseSequence());
@@ skipping 168 matching lines @@
                   (packet->GetBaseTimeUs() + delta_vec[0]) / 1000);
         EXPECT_EQ(kTimeoutTimeMs - kBaseTimeMs, delta_vec[1] / 1000);
         EXPECT_EQ(1, delta_vec[2] / 1000);
         return true;
       }));
 
   Process();
 }
 
 }  // namespace webrtc