Add a rate tracker that tracks rate over a given interval split up into buckets that accumulate uni…

webrtc/base/bucketratetracker_unittest.cc

Index: webrtc/base/bucketratetracker_unittest.cc
diff --git a/webrtc/base/ratetracker_unittest.cc b/webrtc/base/bucketratetracker_unittest.cc
similarity index 56%
copy from webrtc/base/ratetracker_unittest.cc
copy to webrtc/base/bucketratetracker_unittest.cc
index 1c20fd05a2732c7e14e61713fbe3da6d645f5bd5..5fb80877c7827e24cba3e0844dcbb966a805c628 100644
--- a/webrtc/base/ratetracker_unittest.cc
+++ b/webrtc/base/bucketratetracker_unittest.cc
@@ -1,5 +1,5 @@
 /*
- *  Copyright 2010 The WebRTC Project Authors. All rights reserved.
+ *  Copyright 2015 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
@@ -9,13 +9,13 @@
  */
 
 #include "webrtc/base/gunit.h"
-#include "webrtc/base/ratetracker.h"
+#include "webrtc/base/bucketratetracker.h"
 
 namespace rtc {
 
-class RateTrackerForTest : public RateTracker {
+class BucketRateTrackerForTest : public BucketRateTracker {
  public:
-  RateTrackerForTest() : time_(0) {}
+  BucketRateTrackerForTest() : BucketRateTracker(100u, 10u), time_(0) {}
   virtual uint32 Time() const { return time_; }
   void AdvanceTime(uint32 delta) { time_ += delta; }
 
@@ -23,9 +23,34 @@ class RateTrackerForTest : public RateTracker {
   uint32 time_;
 };
 
-TEST(RateTrackerTest, TestBasics) {
-  RateTrackerForTest tracker;
-  EXPECT_EQ(0U, tracker.total_units());
+TEST(BucketRateTrackerTest, Test30FPS) {
+  BucketRateTrackerForTest tracker;
+
+  for (int i = 0; i < 100; ++i) {
+    tracker.AdvanceTime(33);
+    if (i % 3 == 0) {
+      tracker.AdvanceTime(1);
+    }
+    tracker.Update(1);
+  }
+  EXPECT_EQ(30u, tracker.units_second());
+}
+
+TEST(BucketRateTrackerTest, Test60FPS) {
+  BucketRateTrackerForTest tracker;
+
+  for (int i = 0; i < 100; ++i) {
+    tracker.AdvanceTime(16);
+    if (i % 3 != 0) {
+      tracker.AdvanceTime(1);
+    }
+    tracker.Update(1);
+  }
+  EXPECT_EQ(60u, tracker.units_second());
+}
+
+TEST(BucketRateTrackerTest, TestRateTrackerBasics) {
+  BucketRateTrackerForTest tracker;
   EXPECT_EQ(0U, tracker.units_second());
 
   // Add a sample.
@@ -33,35 +58,30 @@ TEST(RateTrackerTest, TestBasics) {
   // Advance the clock by 100 ms.
   tracker.AdvanceTime(100);
   // total_units should advance, but units_second should stay 0.
-  EXPECT_EQ(1234U, tracker.total_units());
   EXPECT_EQ(0U, tracker.units_second());
 
   // Repeat.
   tracker.Update(1234);
   tracker.AdvanceTime(100);
-  EXPECT_EQ(1234U * 2, tracker.total_units());
   EXPECT_EQ(0U, tracker.units_second());
 
   // Advance the clock by 800 ms, so we've elapsed a full second.
   // units_second should now be filled in properly.
   tracker.AdvanceTime(800);
-  EXPECT_EQ(1234U * 2, tracker.total_units());
   EXPECT_EQ(1234U * 2, tracker.units_second());
 
   // Poll the tracker again immediately. The reported rate should stay the same.
-  EXPECT_EQ(1234U * 2, tracker.total_units());
   EXPECT_EQ(1234U * 2, tracker.units_second());
 
   // Do nothing and advance by a second. We should drop down to zero.
   tracker.AdvanceTime(1000);
-  EXPECT_EQ(1234U * 2, tracker.total_units());
   EXPECT_EQ(0U, tracker.units_second());
 
   // Send a bunch of data at a constant rate for 5.5 "seconds".
   // We should report the rate properly.
   for (int i = 0; i < 5500; i += 100) {
-    tracker.Update(9876U);
     tracker.AdvanceTime(100);
+    tracker.Update(9876U);
   }
   EXPECT_EQ(9876U * 10, tracker.units_second());
 
@@ -71,11 +91,34 @@ TEST(RateTrackerTest, TestBasics) {
   EXPECT_EQ(9876U * 5, tracker.units_second());
 }
 
-TEST(RateTrackerTest, TestGetUnitSecondsAfterInitialValue) {
-  RateTrackerForTest tracker;
+TEST(BucketRateTrackerTest, TestGetUnitSecondsAfterInitialValue) {
+  BucketRateTrackerForTest tracker;
   tracker.Update(1234);
   tracker.AdvanceTime(1000);
   EXPECT_EQ(1234u, tracker.units_second());
 }
 
+class IntervalRateTrackerForTest : public IntervalRateTracker {
+ public:
+  IntervalRateTrackerForTest() : IntervalRateTracker(15u), time_(0) {}
+  virtual uint32 Time() const { return time_; }
+  void AdvanceTime(uint32 delta) { time_ += delta; }
+
+ private:
+  uint32 time_;
+};
+
+TEST(IntervalRateTrackerTest, Test30FPS) {
+  IntervalRateTrackerForTest tracker;
+
+  for (int i = 0; i < 30*30; ++i) {
+    tracker.AdvanceTime(33);
+    if (i % 3 == 0) {
+      tracker.AdvanceTime(1);
+    }
+    tracker.Update(1);
+  }
+  EXPECT_EQ(30u, tracker.units_second());
+}
+
 }  // namespace rtc