Making FakeNetworkPipe demux audio and video packets.

webrtc/test/fake_network_pipe_unittest.cc

 /*
  *  Copyright (c) 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.
  */
 
 #include <memory>
 
 #include "webrtc/call/call.h"
+#include "webrtc/modules/rtp_rtcp/include/rtp_header_parser.h"
 #include "webrtc/system_wrappers/include/clock.h"
 #include "webrtc/test/fake_network_pipe.h"
 #include "webrtc/test/gmock.h"
 #include "webrtc/test/gtest.h"
 
 using ::testing::_;
 using ::testing::AnyNumber;
 using ::testing::Return;
 using ::testing::Invoke;
 
 namespace webrtc {
 
-class TestReceiver : public PacketReceiver {
+class TestDemuxer : public Demuxer {
  public:
-  TestReceiver() {}
-  virtual ~TestReceiver() {}
-
-  void IncomingPacket(const uint8_t* data, size_t length) {
-    DeliverPacket(MediaType::ANY, data, length, PacketTime());
-    delete [] data;
+  void IncomingPacket(NetworkPacket* packet) {
+    DeliverPacket(packet, PacketTime());
   }
 
-  virtual MOCK_METHOD4(
+  MOCK_METHOD1(SetReceiver, void(PacketReceiver* receiver));
+  MOCK_METHOD2(DeliverPacket,
+               void(const NetworkPacket* packet,
+                    const PacketTime& packet_time));
+};
+
+class ReorderTestDemuxer : public TestDemuxer {
+ public:
+  void DeliverPacket(const NetworkPacket* packet,
+                     const PacketTime& packet_time) override {
+    RTC_DCHECK_GE(packet->data_length(), sizeof(int));
+    int seq_num;
+    memcpy(&seq_num, packet->data(), sizeof(int));
+    delivered_sequence_numbers_.push_back(seq_num);
+  }
+  std::vector<int> delivered_sequence_numbers_;
+};
+
+class MockReceiver : public PacketReceiver {
+ public:
+  MOCK_METHOD4(
       DeliverPacket,
       DeliveryStatus(MediaType, const uint8_t*, size_t, const PacketTime&));
 };
 
-class ReorderTestReceiver : public TestReceiver {
- public:
-  ReorderTestReceiver() {}
-  virtual ~ReorderTestReceiver() {}
-
-  DeliveryStatus DeliverPacket(MediaType media_type,
-                               const uint8_t* packet,
-                               size_t length,
-                               const PacketTime& packet_time) override {
-    int seq_num;
-    memcpy(&seq_num, packet, sizeof(int));
-    delivered_sequence_numbers_.push_back(seq_num);
-    return PacketReceiver::DELIVERY_OK;
-  }
-  std::vector<int> delivered_sequence_numbers_;
-};
-
 class FakeNetworkPipeTest : public ::testing::Test {
  public:
   FakeNetworkPipeTest() : fake_clock_(12345) {}
 
  protected:
-  virtual void SetUp() {
-    receiver_.reset(new TestReceiver());
-    ON_CALL(*receiver_, DeliverPacket(_, _, _, _))
-        .WillByDefault(Return(PacketReceiver::DELIVERY_OK));
-  }
-
-  virtual void TearDown() {
-  }
-
   void SendPackets(FakeNetworkPipe* pipe, int number_packets, int packet_size) {
     RTC_DCHECK_GE(packet_size, sizeof(int));
     std::unique_ptr<uint8_t[]> packet(new uint8_t[packet_size]);
     for (int i = 0; i < number_packets; ++i) {
       // Set a sequence number for the packets by
       // using the first bytes in the packet.
       memcpy(packet.get(), &i, sizeof(int));
       pipe->SendPacket(packet.get(), packet_size);
     }
   }
 
   int PacketTimeMs(int capacity_kbps, int packet_size) const {
     return 8 * packet_size / capacity_kbps;
   }
 
   SimulatedClock fake_clock_;
-  std::unique_ptr<TestReceiver> receiver_;
 };
 
-void DeleteMemory(uint8_t* data, int length) { delete [] data; }
-
 // Test the capacity link and verify we get as many packets as we expect.
 TEST_F(FakeNetworkPipeTest, CapacityTest) {
   FakeNetworkPipe::Config config;
   config.queue_length_packets = 20;
   config.link_capacity_kbps = 80;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::VIDEO));
-  pipe->SetReceiver(receiver_.get());
+  TestDemuxer* demuxer = new TestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   // Add 10 packets of 1000 bytes, = 80 kb, and verify it takes one second to
   // get through the pipe.
   const int kNumPackets = 10;
   const int kPacketSize = 1000;
-  SendPackets(pipe.get(), kNumPackets , kPacketSize);
+  SendPackets(pipe.get(), kNumPackets, kPacketSize);
 
   // Time to get one packet through the link.
   const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
                                          kPacketSize);
 
   // Time haven't increased yet, so we souldn't get any packets.
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(0);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(0);
   pipe->Process();
 
   // Advance enough time to release one packet.
   fake_clock_.AdvanceTimeMilliseconds(kPacketTimeMs);
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(1);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
   pipe->Process();
 
   // Release all but one packet
   fake_clock_.AdvanceTimeMilliseconds(9 * kPacketTimeMs - 1);
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(8);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(8);
   pipe->Process();
 
   // And the last one.
   fake_clock_.AdvanceTimeMilliseconds(1);
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(1);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
   pipe->Process();
 }
 
 // Test the extra network delay.
 TEST_F(FakeNetworkPipeTest, ExtraDelayTest) {
   FakeNetworkPipe::Config config;
   config.queue_length_packets = 20;
   config.queue_delay_ms = 100;
   config.link_capacity_kbps = 80;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::AUDIO));
-  pipe->SetReceiver(receiver_.get());
+  TestDemuxer* demuxer = new TestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   const int kNumPackets = 2;
   const int kPacketSize = 1000;
-  SendPackets(pipe.get(), kNumPackets , kPacketSize);
+  SendPackets(pipe.get(), kNumPackets, kPacketSize);
 
   // Time to get one packet through the link.
   const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
                                          kPacketSize);
 
   // Increase more than kPacketTimeMs, but not more than the extra delay.
   fake_clock_.AdvanceTimeMilliseconds(kPacketTimeMs);
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::AUDIO, _, _, _)).Times(0);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(0);
   pipe->Process();
 
   // Advance the network delay to get the first packet.
   fake_clock_.AdvanceTimeMilliseconds(config.queue_delay_ms);
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::AUDIO, _, _, _)).Times(1);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
   pipe->Process();
 
   // Advance one more kPacketTimeMs to get the last packet.
   fake_clock_.AdvanceTimeMilliseconds(kPacketTimeMs);
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::AUDIO, _, _, _)).Times(1);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
   pipe->Process();
 }
 
 // Test the number of buffers and packets are dropped when sending too many
 // packets too quickly.
 TEST_F(FakeNetworkPipeTest, QueueLengthTest) {
   FakeNetworkPipe::Config config;
   config.queue_length_packets = 2;
   config.link_capacity_kbps = 80;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::VIDEO));
-  pipe->SetReceiver(receiver_.get());
+  TestDemuxer* demuxer = new TestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   const int kPacketSize = 1000;
   const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
                                          kPacketSize);
 
   // Send three packets and verify only 2 are delivered.
   SendPackets(pipe.get(), 3, kPacketSize);
 
   // Increase time enough to deliver all three packets, verify only two are
   // delivered.
   fake_clock_.AdvanceTimeMilliseconds(3 * kPacketTimeMs);
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(2);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(2);
   pipe->Process();
 }
 
 // Test we get statistics as expected.
 TEST_F(FakeNetworkPipeTest, StatisticsTest) {
   FakeNetworkPipe::Config config;
   config.queue_length_packets = 2;
   config.queue_delay_ms = 20;
   config.link_capacity_kbps = 80;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::VIDEO));
-  pipe->SetReceiver(receiver_.get());
+  TestDemuxer* demuxer = new TestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   const int kPacketSize = 1000;
   const int kPacketTimeMs = PacketTimeMs(config.link_capacity_kbps,
                                          kPacketSize);
 
   // Send three packets and verify only 2 are delivered.
   SendPackets(pipe.get(), 3, kPacketSize);
   fake_clock_.AdvanceTimeMilliseconds(3 * kPacketTimeMs +
                                       config.queue_delay_ms);
 
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(2);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(2);
   pipe->Process();
 
   // Packet 1: kPacketTimeMs + config.queue_delay_ms,
   // packet 2: 2 * kPacketTimeMs + config.queue_delay_ms => 170 ms average.
   EXPECT_EQ(pipe->AverageDelay(), 170);
   EXPECT_EQ(pipe->sent_packets(), 2u);
   EXPECT_EQ(pipe->dropped_packets(), 1u);
   EXPECT_EQ(pipe->PercentageLoss(), 1/3.f);
 }
 
 // Change the link capacity half-way through the test and verify that the
 // delivery times change accordingly.
 TEST_F(FakeNetworkPipeTest, ChangingCapacityWithEmptyPipeTest) {
   FakeNetworkPipe::Config config;
   config.queue_length_packets = 20;
   config.link_capacity_kbps = 80;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::VIDEO));
-  pipe->SetReceiver(receiver_.get());
+  TestDemuxer* demuxer = new TestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   // Add 10 packets of 1000 bytes, = 80 kb, and verify it takes one second to
   // get through the pipe.
   const int kNumPackets = 10;
   const int kPacketSize = 1000;
   SendPackets(pipe.get(), kNumPackets, kPacketSize);
 
   // Time to get one packet through the link.
   int packet_time_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
 
   // Time hasn't increased yet, so we souldn't get any packets.
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(0);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(0);
   pipe->Process();
 
   // Advance time in steps to release one packet at a time.
   for (int i = 0; i < kNumPackets; ++i) {
     fake_clock_.AdvanceTimeMilliseconds(packet_time_ms);
-    EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(1);
+    EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
     pipe->Process();
   }
 
   // Change the capacity.
   config.link_capacity_kbps /= 2;  // Reduce to 50%.
   pipe->SetConfig(config);
 
   // Add another 10 packets of 1000 bytes, = 80 kb, and verify it takes two
   // seconds to get them through the pipe.
   SendPackets(pipe.get(), kNumPackets, kPacketSize);
 
   // Time to get one packet through the link.
   packet_time_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
 
   // Time hasn't increased yet, so we souldn't get any packets.
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(0);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(0);
   pipe->Process();
 
   // Advance time in steps to release one packet at a time.
   for (int i = 0; i < kNumPackets; ++i) {
     fake_clock_.AdvanceTimeMilliseconds(packet_time_ms);
-    EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(1);
+    EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
     pipe->Process();
   }
 
   // Check that all the packets were sent.
   EXPECT_EQ(static_cast<size_t>(2 * kNumPackets), pipe->sent_packets());
   fake_clock_.AdvanceTimeMilliseconds(pipe->TimeUntilNextProcess());
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::VIDEO, _, _, _)).Times(0);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(0);
   pipe->Process();
 }
 
 // Change the link capacity half-way through the test and verify that the
 // delivery times change accordingly.
 TEST_F(FakeNetworkPipeTest, ChangingCapacityWithPacketsInPipeTest) {
   FakeNetworkPipe::Config config;
   config.queue_length_packets = 20;
   config.link_capacity_kbps = 80;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::AUDIO));
-  pipe->SetReceiver(receiver_.get());
+  TestDemuxer* demuxer = new TestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   // Add 10 packets of 1000 bytes, = 80 kb.
   const int kNumPackets = 10;
   const int kPacketSize = 1000;
   SendPackets(pipe.get(), kNumPackets, kPacketSize);
 
   // Time to get one packet through the link at the initial speed.
   int packet_time_1_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
 
   // Change the capacity.
   config.link_capacity_kbps *= 2;  // Double the capacity.
   pipe->SetConfig(config);
 
   // Add another 10 packets of 1000 bytes, = 80 kb, and verify it takes two
   // seconds to get them through the pipe.
   SendPackets(pipe.get(), kNumPackets, kPacketSize);
 
   // Time to get one packet through the link at the new capacity.
   int packet_time_2_ms = PacketTimeMs(config.link_capacity_kbps, kPacketSize);
 
   // Time hasn't increased yet, so we souldn't get any packets.
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::AUDIO, _, _, _)).Times(0);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(0);
   pipe->Process();
 
   // Advance time in steps to release one packet at a time.
   for (int i = 0; i < kNumPackets; ++i) {
     fake_clock_.AdvanceTimeMilliseconds(packet_time_1_ms);
-    EXPECT_CALL(*receiver_, DeliverPacket(MediaType::AUDIO, _, _, _)).Times(1);
+    EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
     pipe->Process();
   }
 
   // Advance time in steps to release one packet at a time.
   for (int i = 0; i < kNumPackets; ++i) {
     fake_clock_.AdvanceTimeMilliseconds(packet_time_2_ms);
-    EXPECT_CALL(*receiver_, DeliverPacket(MediaType::AUDIO, _, _, _)).Times(1);
+    EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(1);
     pipe->Process();
   }
 
   // Check that all the packets were sent.
   EXPECT_EQ(static_cast<size_t>(2 * kNumPackets), pipe->sent_packets());
   fake_clock_.AdvanceTimeMilliseconds(pipe->TimeUntilNextProcess());
-  EXPECT_CALL(*receiver_, DeliverPacket(MediaType::AUDIO, _, _, _)).Times(0);
+  EXPECT_CALL(*demuxer, DeliverPacket(_, _)).Times(0);
   pipe->Process();
 }
 
 // At first disallow reordering and then allow reordering.
 TEST_F(FakeNetworkPipeTest, DisallowReorderingThenAllowReordering) {
   FakeNetworkPipe::Config config;
   config.queue_length_packets = 1000;
   config.link_capacity_kbps = 800;
   config.queue_delay_ms = 100;
   config.delay_standard_deviation_ms = 10;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::VIDEO));
-  ReorderTestReceiver* receiver = new ReorderTestReceiver();
-  receiver_.reset(receiver);
-  pipe->SetReceiver(receiver_.get());
+  ReorderTestDemuxer* demuxer = new ReorderTestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   const uint32_t kNumPackets = 100;
   const int kPacketSize = 10;
   SendPackets(pipe.get(), kNumPackets, kPacketSize);
   fake_clock_.AdvanceTimeMilliseconds(1000);
   pipe->Process();
 
   // Confirm that all packets have been delivered in order.
-  EXPECT_EQ(kNumPackets, receiver->delivered_sequence_numbers_.size());
+  EXPECT_EQ(kNumPackets, demuxer->delivered_sequence_numbers_.size());
   int last_seq_num = -1;
-  for (int seq_num : receiver->delivered_sequence_numbers_) {
+  for (int seq_num : demuxer->delivered_sequence_numbers_) {
     EXPECT_GT(seq_num, last_seq_num);
     last_seq_num = seq_num;
   }
 
   config.allow_reordering = true;
   pipe->SetConfig(config);
   SendPackets(pipe.get(), kNumPackets, kPacketSize);
   fake_clock_.AdvanceTimeMilliseconds(1000);
-  receiver->delivered_sequence_numbers_.clear();
+  demuxer->delivered_sequence_numbers_.clear();
   pipe->Process();
 
   // Confirm that all packets have been delivered
   // and that reordering has occured.
-  EXPECT_EQ(kNumPackets, receiver->delivered_sequence_numbers_.size());
+  EXPECT_EQ(kNumPackets, demuxer->delivered_sequence_numbers_.size());
   bool reordering_has_occured = false;
   last_seq_num = -1;
-  for (int seq_num : receiver->delivered_sequence_numbers_) {
+  for (int seq_num : demuxer->delivered_sequence_numbers_) {
     if (last_seq_num > seq_num) {
       reordering_has_occured = true;
       break;
     }
     last_seq_num = seq_num;
   }
   EXPECT_TRUE(reordering_has_occured);
 }
 
 TEST_F(FakeNetworkPipeTest, BurstLoss) {
   const int kLossPercent = 5;
   const int kAvgBurstLength = 3;
   const int kNumPackets = 10000;
   const int kPacketSize = 10;
 
   FakeNetworkPipe::Config config;
   config.queue_length_packets = kNumPackets;
   config.loss_percent = kLossPercent;
   config.avg_burst_loss_length = kAvgBurstLength;
-  std::unique_ptr<FakeNetworkPipe> pipe(
-      new FakeNetworkPipe(&fake_clock_, config, MediaType::VIDEO));
-  ReorderTestReceiver* receiver = new ReorderTestReceiver();
-  receiver_.reset(receiver);
-  pipe->SetReceiver(receiver_.get());
+  ReorderTestDemuxer* demuxer = new ReorderTestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
 
   SendPackets(pipe.get(), kNumPackets, kPacketSize);
   fake_clock_.AdvanceTimeMilliseconds(1000);
   pipe->Process();
 
   // Check that the average loss is |kLossPercent| percent.
-  int lost_packets = kNumPackets - receiver->delivered_sequence_numbers_.size();
+  int lost_packets = kNumPackets - demuxer->delivered_sequence_numbers_.size();
   double loss_fraction = lost_packets / static_cast<double>(kNumPackets);
 
   EXPECT_NEAR(kLossPercent / 100.0, loss_fraction, 0.05);
 
   // Find the number of bursts that has occurred.
-  size_t received_packets = receiver->delivered_sequence_numbers_.size();
+  size_t received_packets = demuxer->delivered_sequence_numbers_.size();
   int num_bursts = 0;
   for (size_t i = 0; i < received_packets - 1; ++i) {
-    int diff = receiver->delivered_sequence_numbers_[i + 1] -
-               receiver->delivered_sequence_numbers_[i];
+    int diff = demuxer->delivered_sequence_numbers_[i + 1] -
+               demuxer->delivered_sequence_numbers_[i];
     if (diff > 1)
       ++num_bursts;
   }
 
   double average_burst_length = static_cast<double>(lost_packets) / num_bursts;
 
   EXPECT_NEAR(kAvgBurstLength, average_burst_length, 0.3);
 }
+
+TEST_F(FakeNetworkPipeTest, SetReceiver) {
+  FakeNetworkPipe::Config config;
+  TestDemuxer* demuxer = new TestDemuxer();
+  std::unique_ptr<FakeNetworkPipe> pipe(new FakeNetworkPipe(
+      &fake_clock_, config, std::unique_ptr<Demuxer>(demuxer)));
+  MockReceiver packet_receiver;
+  EXPECT_CALL(*demuxer, SetReceiver(&packet_receiver)).Times(1);
+  pipe->SetReceiver(&packet_receiver);
+}
+
+TEST(DemuxerImplTest, Demuxing) {
+  constexpr uint8_t kVideoPayloadType = 100;
+  constexpr uint8_t kAudioPayloadType = 101;
+  constexpr int64_t kTimeNow = 12345;
+  constexpr int64_t kArrivalTime = kTimeNow - 1;
+  constexpr size_t kPacketSize = 10;
+  DemuxerImpl demuxer({{kVideoPayloadType, MediaType::VIDEO},
+                       {kAudioPayloadType, MediaType::AUDIO}});
+
+  MockReceiver mock_receiver;
+  demuxer.SetReceiver(&mock_receiver);
+
+  std::vector<uint8_t> data(kPacketSize);
+  data[1] = kVideoPayloadType;
+  std::unique_ptr<NetworkPacket> packet(
+      new NetworkPacket(&data[0], kPacketSize, kTimeNow, kArrivalTime));
+  EXPECT_CALL(mock_receiver, DeliverPacket(MediaType::VIDEO, _, _, _))
+      .WillOnce(Return(PacketReceiver::DELIVERY_OK));
+  demuxer.DeliverPacket(packet.get(), PacketTime());
+
+  data[1] = kAudioPayloadType;
+  packet.reset(
+      new NetworkPacket(&data[0], kPacketSize, kTimeNow, kArrivalTime));
+  EXPECT_CALL(mock_receiver, DeliverPacket(MediaType::AUDIO, _, _, _))
+      .WillOnce(Return(PacketReceiver::DELIVERY_OK));
+  demuxer.DeliverPacket(packet.get(), PacketTime());
+}
+
 }  // namespace webrtc