1 files changed, 153 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/congestion_controller/goog_cc/trendline_estimator_unittest.cc b/third_party/libwebrtc/modules/congestion_controller/goog_cc/trendline_estimator_unittest.cc
new file mode 100644
index 0000000000..b7a3089ba2
--- /dev/null
+++ b/third_party/libwebrtc/modules/congestion_controller/goog_cc/trendline_estimator_unittest.cc
@@ -0,0 +1,153 @@
+/*
+ *  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 "modules/congestion_controller/goog_cc/trendline_estimator.h"
+
+#include <algorithm>
+#include <cstddef>
+#include <cstdint>
+#include <vector>
+
+#include "api/network_state_predictor.h"
+#include "api/transport/field_trial_based_config.h"
+#include "rtc_base/checks.h"
+#include "test/gtest.h"
+
+namespace webrtc {
+namespace {
+
+class PacketTimeGenerator {
+ public:
+  PacketTimeGenerator(int64_t initial_clock, double time_between_packets)
+      : initial_clock_(initial_clock),
+        time_between_packets_(time_between_packets),
+        packets_(0) {}
+  int64_t operator()() {
+    return initial_clock_ + time_between_packets_ * packets_++;
+  }
+
+ private:
+  const int64_t initial_clock_;
+  const double time_between_packets_;
+  size_t packets_;
+};
+
+class TrendlineEstimatorTest : public testing::Test {
+ public:
+  TrendlineEstimatorTest()
+      : send_times(kPacketCount),
+        recv_times(kPacketCount),
+        packet_sizes(kPacketCount),
+        config(),
+        estimator(&config, nullptr),
+        count(1) {
+    std::fill(packet_sizes.begin(), packet_sizes.end(), kPacketSizeBytes);
+  }
+
+  void RunTestUntilStateChange() {
+    RTC_DCHECK_EQ(send_times.size(), kPacketCount);
+    RTC_DCHECK_EQ(recv_times.size(), kPacketCount);
+    RTC_DCHECK_EQ(packet_sizes.size(), kPacketCount);
+    RTC_DCHECK_GE(count, 1);
+    RTC_DCHECK_LT(count, kPacketCount);
+
+    auto initial_state = estimator.State();
+    for (; count < kPacketCount; count++) {
+      double recv_delta = recv_times[count] - recv_times[count - 1];
+      double send_delta = send_times[count] - send_times[count - 1];
+      estimator.Update(recv_delta, send_delta, send_times[count],
+                       recv_times[count], packet_sizes[count], true);
+      if (estimator.State() != initial_state) {
+        return;
+      }
+    }
+  }
+
+ protected:
+  const size_t kPacketCount = 25;
+  const size_t kPacketSizeBytes = 1200;
+  std::vector<int64_t> send_times;
+  std::vector<int64_t> recv_times;
+  std::vector<size_t> packet_sizes;
+  const FieldTrialBasedConfig config;
+  TrendlineEstimator estimator;
+  size_t count;
+};
+}  // namespace
+
+TEST_F(TrendlineEstimatorTest, Normal) {
+  PacketTimeGenerator send_time_generator(123456789 /*initial clock*/,
+                                          20 /*20 ms between sent packets*/);
+  std::generate(send_times.begin(), send_times.end(), send_time_generator);
+
+  PacketTimeGenerator recv_time_generator(987654321 /*initial clock*/,
+                                          20 /*delivered at the same pace*/);
+  std::generate(recv_times.begin(), recv_times.end(), recv_time_generator);
+
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwNormal);
+  RunTestUntilStateChange();
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwNormal);
+  EXPECT_EQ(count, kPacketCount);  // All packets processed
+}
+
+TEST_F(TrendlineEstimatorTest, Overusing) {
+  PacketTimeGenerator send_time_generator(123456789 /*initial clock*/,
+                                          20 /*20 ms between sent packets*/);
+  std::generate(send_times.begin(), send_times.end(), send_time_generator);
+
+  PacketTimeGenerator recv_time_generator(987654321 /*initial clock*/,
+                                          1.1 * 20 /*10% slower delivery*/);
+  std::generate(recv_times.begin(), recv_times.end(), recv_time_generator);
+
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwNormal);
+  RunTestUntilStateChange();
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwOverusing);
+  RunTestUntilStateChange();
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwOverusing);
+  EXPECT_EQ(count, kPacketCount);  // All packets processed
+}
+
+TEST_F(TrendlineEstimatorTest, Underusing) {
+  PacketTimeGenerator send_time_generator(123456789 /*initial clock*/,
+                                          20 /*20 ms between sent packets*/);
+  std::generate(send_times.begin(), send_times.end(), send_time_generator);
+
+  PacketTimeGenerator recv_time_generator(987654321 /*initial clock*/,
+                                          0.85 * 20 /*15% faster delivery*/);
+  std::generate(recv_times.begin(), recv_times.end(), recv_time_generator);
+
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwNormal);
+  RunTestUntilStateChange();
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwUnderusing);
+  RunTestUntilStateChange();
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwUnderusing);
+  EXPECT_EQ(count, kPacketCount);  // All packets processed
+}
+
+TEST_F(TrendlineEstimatorTest, IncludesSmallPacketsByDefault) {
+  PacketTimeGenerator send_time_generator(123456789 /*initial clock*/,
+                                          20 /*20 ms between sent packets*/);
+  std::generate(send_times.begin(), send_times.end(), send_time_generator);
+
+  PacketTimeGenerator recv_time_generator(987654321 /*initial clock*/,
+                                          1.1 * 20 /*10% slower delivery*/);
+  std::generate(recv_times.begin(), recv_times.end(), recv_time_generator);
+
+  std::fill(packet_sizes.begin(), packet_sizes.end(), 100);
+
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwNormal);
+  RunTestUntilStateChange();
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwOverusing);
+  RunTestUntilStateChange();
+  EXPECT_EQ(estimator.State(), BandwidthUsage::kBwOverusing);
+  EXPECT_EQ(count, kPacketCount);  // All packets processed
+}
+
+}  // namespace webrtc