Remove SendPacer from ViEEncoder and make sure SendPacer starts at a valid bitrate

webrtc/modules/congestion_controller/congestion_controller_unittest.cc

+/*
+ *  Copyright (c) 2016 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/mock/mock_paced_sender.h"
+#include "webrtc/modules/congestion_controller/include/congestion_controller.h"
+#include "webrtc/modules/congestion_controller/include/mock/mock_congestion_controller.h"
+#include "webrtc/modules/remote_bitrate_estimator/include/mock/mock_remote_bitrate_observer.h"
+#include "webrtc/system_wrappers/include/clock.h"
+
+using testing::_;
+using testing::NiceMock;
+using testing::Return;
+using testing::SaveArg;
+using testing::StrictMock;
+
+namespace webrtc {
+namespace test {
+
+class CongestionControllerTest : public ::testing::Test {
+ protected:
+  CongestionControllerTest() : clock_(123456) {}
+  ~CongestionControllerTest() override {}
+
+  void SetUp() override {
+    pacer_ = new NiceMock<MockPacedSender>();
+    std::unique_ptr<PacedSender> pacer(pacer_);  // Passes ownership.
+    std::unique_ptr<PacketRouter> packet_router(new PacketRouter());
+    controller_.reset(
+        new CongestionController(&clock_, &observer_, &remote_bitrate_observer_,
+                                 std::move(packet_router), std::move(pacer)));
+    bandwidth_observer_.reset(
+        controller_->GetBitrateController()->CreateRtcpBandwidthObserver());
+
+    // Set the initial bitrate estimate and expect the |observer| and |pacer_|
+    // to be updated.
+    EXPECT_CALL(observer_, OnNetworkChanged(kInitialBitrateBps, _, _));
+    EXPECT_CALL(*pacer_, SetEstimatedBitrate(kInitialBitrateBps));
+    controller_->SetBweBitrates(0, kInitialBitrateBps, 5 * kInitialBitrateBps);
+  }
+
+  SimulatedClock clock_;
+  StrictMock<MockCongestionObserver> observer_;
+  NiceMock<MockPacedSender>* pacer_;
+  NiceMock<MockRemoteBitrateObserver> remote_bitrate_observer_;
+  std::unique_ptr<RtcpBandwidthObserver> bandwidth_observer_;
+  std::unique_ptr<CongestionController> controller_;
+  const uint32_t kInitialBitrateBps = 60000;
+};
+
+TEST_F(CongestionControllerTest, OnNetworkChanged) {
+  // Test no change.
+  clock_.AdvanceTimeMilliseconds(25);
+  controller_->Process();
+
+  EXPECT_CALL(observer_, OnNetworkChanged(kInitialBitrateBps * 2, _, _));
+  EXPECT_CALL(*pacer_, SetEstimatedBitrate(kInitialBitrateBps * 2));
+  bandwidth_observer_->OnReceivedEstimatedBitrate(kInitialBitrateBps * 2);
+  clock_.AdvanceTimeMilliseconds(25);
+  controller_->Process();
+
+  EXPECT_CALL(observer_, OnNetworkChanged(kInitialBitrateBps, _, _));
+  EXPECT_CALL(*pacer_, SetEstimatedBitrate(kInitialBitrateBps));
+  bandwidth_observer_->OnReceivedEstimatedBitrate(kInitialBitrateBps);
+  clock_.AdvanceTimeMilliseconds(25);
+  controller_->Process();
+}
+
+TEST_F(CongestionControllerTest, OnSendQueueFull) {
+  EXPECT_CALL(*pacer_, ExpectedQueueTimeMs())
+      .WillOnce(Return(PacedSender::kMaxQueueLengthMs + 1));
+
+  EXPECT_CALL(observer_, OnNetworkChanged(0, _, _));
+  controller_->Process();
+
+  // Let the pacer not be full next time the controller checks.
+  EXPECT_CALL(*pacer_, ExpectedQueueTimeMs())
+      .WillOnce(Return(PacedSender::kMaxQueueLengthMs - 1));
+
+  EXPECT_CALL(observer_, OnNetworkChanged(kInitialBitrateBps, _, _));
+  controller_->Process();
+}
+
+TEST_F(CongestionControllerTest, OnSendQueueFullAndEstimateChange) {
+  EXPECT_CALL(*pacer_, ExpectedQueueTimeMs())
+      .WillOnce(Return(PacedSender::kMaxQueueLengthMs + 1));
+  EXPECT_CALL(observer_, OnNetworkChanged(0, _, _));
+  controller_->Process();
+
+  // Receive new estimate but let the queue still be full.
+  bandwidth_observer_->OnReceivedEstimatedBitrate(kInitialBitrateBps * 2);
+  EXPECT_CALL(*pacer_, ExpectedQueueTimeMs())
+      .WillOnce(Return(PacedSender::kMaxQueueLengthMs + 1));
+  //  The send pacer should get the new estimate though.
+  EXPECT_CALL(*pacer_, SetEstimatedBitrate(kInitialBitrateBps * 2));
+  clock_.AdvanceTimeMilliseconds(25);
+  controller_->Process();
+
+  // Let the pacer not be full next time the controller checks.
+  // |OnNetworkChanged| should be called with the new estimate.
+  EXPECT_CALL(*pacer_, ExpectedQueueTimeMs())
+      .WillOnce(Return(PacedSender::kMaxQueueLengthMs - 1));
+  EXPECT_CALL(observer_, OnNetworkChanged(kInitialBitrateBps * 2, _, _));
+  clock_.AdvanceTimeMilliseconds(25);
+  controller_->Process();
+}
+
+}  // namespace test
+}  // namespace webrtc