Test and fix for huge bwe drop after alr state.

webrtc/modules/congestion_controller/acknowledge_bitrate_estimator_unittest.cc

+/*
+ *  Copyright (c) 2017 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 "webrtc/modules/congestion_controller/acknowledge_bitrate_estimator.h"
+
+#include "webrtc/base/fakeclock.h"
+#include "webrtc/base/ptr_util.h"
+#include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h"
+#include "webrtc/test/gmock.h"
+#include "webrtc/test/gtest.h"
+
+using testing::_;
+using testing::NiceMock;
+using testing::InSequence;
+
+namespace webrtc {
+
+namespace {
+class MockBitrateEstimator : public BitrateEstimator {
+ public:
+  ~MockBitrateEstimator() { Die(); }
+
+  MOCK_METHOD0(Die, void());
+  MOCK_METHOD2(Update, void(int64_t now_ms, int bytes));
+  MOCK_CONST_METHOD0(bitrate_bps, rtc::Optional<uint32_t>());
+};
+
+struct AcknowledgedBitrateEstimatorTestStates {
+  std::unique_ptr<AcknowledgedBitrateEstimator> acknowledged_bitrate_estimator;
+  MockBitrateEstimator* bitrate_estimator;
+};
+
+AcknowledgedBitrateEstimatorTestStates CreateTestStates() {
+  AcknowledgedBitrateEstimatorTestStates states;
+  states.acknowledged_bitrate_estimator =
+      rtc::MakeUnique<AcknowledgedBitrateEstimator>([&states]() {
+        auto bitrate_estimator =
+            rtc::MakeUnique<NiceMock<MockBitrateEstimator>>();
+        states.bitrate_estimator = bitrate_estimator.get();
+        return bitrate_estimator;
+      });
+  EXPECT_CALL(*states.bitrate_estimator, Die()).Times(1);
+  return states;
+}
+
+constexpr int64_t first_arrival_time_ms = 10;
+constexpr int64_t first_send_time_ms = 10;
+constexpr uint16_t sequence_number = 1;
+constexpr size_t payload_size = 10;
+
+std::vector<PacketFeedback> CreateFeedbackVector() {
+  std::vector<PacketFeedback> packet_feedback_vector;
+  const PacedPacketInfo pacing_info;
+  packet_feedback_vector.push_back(
+      PacketFeedback(first_arrival_time_ms, first_send_time_ms, sequence_number,
+                     payload_size, pacing_info));
+  packet_feedback_vector.push_back(
+      PacketFeedback(first_arrival_time_ms + 10, first_send_time_ms + 10,
+                     sequence_number, payload_size + 10, pacing_info));
+  return packet_feedback_vector;
+}
+
+}  // anonymous namespace
+
+TEST(TestAcknowledgedBitrateEstimator, DontAddPacketsWhichAreNotInSendHistory) {
+  auto states = CreateTestStates();
+  std::vector<PacketFeedback> packet_feedback_vector;
+  packet_feedback_vector.push_back(
+      PacketFeedback(first_arrival_time_ms, sequence_number));
+  EXPECT_CALL(*states.bitrate_estimator, Update(_, _)).Times(0);
+  states.acknowledged_bitrate_estimator->IncomingPacketFeedbackVector(
+      packet_feedback_vector, false);
+}
+
+TEST(TestAcknowledgedBitrateEstimator, UpdateBandwith) {
+  auto states = CreateTestStates();
+  auto packet_feedback_vector = CreateFeedbackVector();
+  {
+    InSequence dummy;
+    EXPECT_CALL(*states.bitrate_estimator,
+                Update(packet_feedback_vector[0].arrival_time_ms,
+                       packet_feedback_vector[0].payload_size))
+        .Times(1);
+    EXPECT_CALL(*states.bitrate_estimator,
+                Update(packet_feedback_vector[1].arrival_time_ms,
+                       packet_feedback_vector[1].payload_size))
+        .Times(1);
+  }
+  states.acknowledged_bitrate_estimator->IncomingPacketFeedbackVector(
+      packet_feedback_vector, false);
+}
+
+TEST(TestAcknowledgedBitrateEstimator,
+     ResetAfterLeafAlrStateAndDontAddOldPackets) {
+  auto states = CreateTestStates();
+  auto packet_feedback_vector = CreateFeedbackVector();
+  states.acknowledged_bitrate_estimator->IncomingPacketFeedbackVector(
+      packet_feedback_vector, true);
+
+  rtc::ScopedFakeClock fake_clock;
+
+  fake_clock.AdvanceTime(
+      rtc::TimeDelta::FromMilliseconds(first_arrival_time_ms + 1));
+  states.acknowledged_bitrate_estimator->IncomingPacketFeedbackVector(
+      std::vector<PacketFeedback>(), false);
+  EXPECT_CALL(*states.bitrate_estimator, Die()).Times(1);
+
+  {
+    InSequence dummy;
+    EXPECT_CALL(*states.bitrate_estimator,
+                Update(packet_feedback_vector[0].arrival_time_ms,
+                       packet_feedback_vector[0].payload_size))
+        .Times(0);
+    EXPECT_CALL(*states.bitrate_estimator,
+                Update(packet_feedback_vector[1].arrival_time_ms,
+                       packet_feedback_vector[1].payload_size))
+        .Times(1);
+  }
+  states.acknowledged_bitrate_estimator->IncomingPacketFeedbackVector(
+      packet_feedback_vector, false);
+}
+
+}  // namespace webrtc