Add AlrDetector

webrtc/modules/congestion_controller/alr_detector_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/gtest/include/gtest/gtest.h"
+#include "webrtc/modules/congestion_controller/alr_detector.h"
+
+namespace {
+
+constexpr int kMeasuredIntervalMs = 110;
+constexpr int kEstimatedBitrateBps = 300000;
+constexpr int kBytesInIntervalAtEstimatedBitrate =
+    (kEstimatedBitrateBps / 8) * kMeasuredIntervalMs / 1000;
+
+}  // namespace
+
+namespace webrtc {
+
+TEST(AlrDetectorTest, ApplicationLimitedWhenLittleDataSent) {
+  AlrDetector alr_detector;
+
+  alr_detector.SetEstimatedBitrate(kEstimatedBitrateBps);
+  for (int i = 0; i < 6; i++)
+    alr_detector.OnBytesSent(0, kMeasuredIntervalMs);
+  EXPECT_EQ(alr_detector.InApplicationLimitedRegion(), true);
+
+  for (int i = 0; i < 6; i++)
+    alr_detector.OnBytesSent(100, kMeasuredIntervalMs);
+  EXPECT_EQ(alr_detector.InApplicationLimitedRegion(), true);
+}
+
+TEST(AlrDetectorTest, NetworkLimitedWhenSendingCloseToEstimate) {
+  AlrDetector alr_detector;
+
+  alr_detector.SetEstimatedBitrate(kEstimatedBitrateBps);
+  for (int i = 0; i < 6; i++)
+    alr_detector.OnBytesSent(kBytesInIntervalAtEstimatedBitrate,
+                             kMeasuredIntervalMs);
+  EXPECT_EQ(alr_detector.InApplicationLimitedRegion(), false);
+}
+
+}  // namespace webrtc