Add metrics regarding concurrent audible tabs in Chromium.

content/browser/media/audible_metrics_unittest.cc

Index: content/browser/media/audible_metrics_unittest.cc
diff --git a/content/browser/media/audible_metrics_unittest.cc b/content/browser/media/audible_metrics_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7864ba5f537968d256213b52861d367a81a757af
--- /dev/null
+++ b/content/browser/media/audible_metrics_unittest.cc
@@ -0,0 +1,342 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/media/audible_metrics.h"
+
+#include "base/metrics/histogram_samples.h"
+#include "base/test/histogram_tester.h"
+#include "base/test/simple_test_clock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace content {
+
+namespace {
+
+static WebContents* WEB_CONTENTS_0 = reinterpret_cast<WebContents*>(0x00);

[whywhat, 2016/01/15 19:01:20]

nit: perhaps you meant something like "const WebContents* const" ?

[DaleCurtis, 2016/01/15 19:02:03]

const these if possible

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

Switched to const.

+static WebContents* WEB_CONTENTS_1 = reinterpret_cast<WebContents*>(0x01);
+static WebContents* WEB_CONTENTS_2 = reinterpret_cast<WebContents*>(0x10);
+static WebContents* WEB_CONTENTS_3 = reinterpret_cast<WebContents*>(0x11);
+
+class AudibleMetricsTest : public testing::Test {
+ public:
+  AudibleMetricsTest() = default;

[whywhat, 2016/01/15 19:01:20]

nit: is this needed? won't it have a default ctor without this?

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

I need the default ctor.

+
+  void SetUp() override {
+    clock_ = new base::SimpleTestClock();
+    clock_->SetNow(base::Time::Now());
+    audible_metrics_.SetClockForTest(
+        scoped_ptr<base::SimpleTestClock>(clock_));
+  }
+
+  void TearDown() override {
+    clock_ = nullptr;

[whywhat, 2016/01/15 19:01:20]

nit: this is probably not needed

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

|clock_| is owned by |audible_metrics_|, I prefer to reset the pointer because
after TearDown() it's pointing in an invalid memory space.

+  }
+
+  base::SimpleTestClock* clock() { return clock_; }
+
+  AudibleMetrics& audible_metrics() {

[DaleCurtis, 2016/01/15 19:02:03]

Don't return non-const& -- use a pointer instead (unless this is now allowed as
part of the blink-chromium style guide changes)

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

Switched to a pointer. Might be allowed now but lets stay consistent ;)

+    return audible_metrics_;
+  };
+
+  scoped_ptr<base::HistogramSamples> GetHistogramSamplesSinceTestStart(
+      const std::string& name) {
+    return histogram_tester_.GetHistogramSamplesSinceCreation(name);
+  }
+
+ private:
+  base::SimpleTestClock* clock_ = nullptr;
+  AudibleMetrics audible_metrics_;
+  base::HistogramTester histogram_tester_;
+};

[DaleCurtis, 2016/01/15 19:02:03]

DISALLOW_COPY_AND_ASSIGN.

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

Done.

+
+}  // anonymous namespace
+
+TEST_F(AudibleMetricsTest, CreateAndKillDoesNothing) {
+  {
+    AudibleMetrics* audible_metrics = new AudibleMetrics();

[DaleCurtis, 2016/01/15 19:02:03]

Just use a scoped_ptr?

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

It looks a bit odd now but why not.

+    delete audible_metrics;
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));
+    EXPECT_EQ(0, samples->TotalCount());
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsInSession"));
+    EXPECT_EQ(0, samples->TotalCount());
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart("Media.Audible.ConcurrentTabsTime"));
+    EXPECT_EQ(0, samples->TotalCount());
+  }
+}
+
+TEST_F(AudibleMetricsTest, AudibleStart) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(0));
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsInSession"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(1));
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart("Media.Audible.ConcurrentTabsTime"));
+    EXPECT_EQ(0, samples->TotalCount());
+  }
+}
+
+TEST_F(AudibleMetricsTest, AudibleStartAndStop) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));

[DaleCurtis, 2016/01/15 19:02:03]

I think the histogram macros prevent you from using a shared public variable,
but for all of these tests you should just make the names top-level consts.

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

Done.

+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(0));
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsInSession"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(1));
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart("Media.Audible.ConcurrentTabsTime"));
+    EXPECT_EQ(0, samples->TotalCount());
+  }
+}
+
+TEST_F(AudibleMetricsTest, AddSameTabIsNoOp) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(0));
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsInSession"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(1));
+  }
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart("Media.Audible.ConcurrentTabsTime"));
+    EXPECT_EQ(0, samples->TotalCount());
+  }
+}
+
+TEST_F(AudibleMetricsTest, RemoveUnknownTabIsNoOp) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+
+  EXPECT_EQ(0, GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsWhenStarting")->TotalCount());
+  EXPECT_EQ(0, GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsInSession")->TotalCount());
+  EXPECT_EQ(0, GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsTime")->TotalCount());
+}
+
+TEST_F(AudibleMetricsTest, ConcurrentTabsInSessionIsIncremental) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_2, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_3, true);
+
+  scoped_ptr<base::HistogramSamples> samples(GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsInSession"));
+  EXPECT_EQ(4, samples->TotalCount());
+  EXPECT_EQ(1, samples->GetCount(1));
+  EXPECT_EQ(1, samples->GetCount(2));
+  EXPECT_EQ(1, samples->GetCount(3));
+  EXPECT_EQ(1, samples->GetCount(4));
+}
+
+TEST_F(AudibleMetricsTest, ConcurrentTabsInSessionKeepTrackOfRemovedTabs) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_2, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_2, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_3, true);
+
+  scoped_ptr<base::HistogramSamples> samples(GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsInSession"));
+  EXPECT_EQ(2, samples->TotalCount());
+  EXPECT_EQ(1, samples->GetCount(1));
+  EXPECT_EQ(1, samples->GetCount(2));
+}
+
+TEST_F(AudibleMetricsTest, ConcurrentTabsInSessionIsNotCountedTwice) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_2, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_3, true);
+
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_2, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_3, false);
+
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_2, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_3, true);
+
+  scoped_ptr<base::HistogramSamples> samples(GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsInSession"));
+  EXPECT_EQ(4, samples->TotalCount());
+  EXPECT_EQ(1, samples->GetCount(1));
+  EXPECT_EQ(1, samples->GetCount(2));
+  EXPECT_EQ(1, samples->GetCount(3));
+  EXPECT_EQ(1, samples->GetCount(4));
+}
+
+TEST_F(AudibleMetricsTest, ConcurrentTabsWhenStartingAddedPerTab) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));
+    EXPECT_EQ(2, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(0));
+    EXPECT_EQ(1, samples->GetCount(1));
+  }
+
+  // Added again: ignored.
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));
+    EXPECT_EQ(2, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(0));
+    EXPECT_EQ(1, samples->GetCount(1));
+  }
+
+  // Removing both.
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, false);
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));
+    EXPECT_EQ(2, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(0));
+    EXPECT_EQ(1, samples->GetCount(1));
+  }
+
+  // Adding them after removed, it is counted.
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart(
+            "Media.Audible.ConcurrentTabsWhenStarting"));
+    EXPECT_EQ(4, samples->TotalCount());
+    EXPECT_EQ(2, samples->GetCount(0));
+    EXPECT_EQ(2, samples->GetCount(1));
+  }
+}
+
+TEST_F(AudibleMetricsTest, ConcurrentTabsTimeRequiresTwoAudibleTabs) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+
+  clock()->Advance(base::TimeDelta::FromMilliseconds(1000));
+
+  // No record because concurrent audbile tabs still running.

[whywhat, 2016/01/15 19:01:20]

nit: s/audbile/audible + one more occurrence below

[mlamouri (slow - plz ping), 2016/01/19 12:18:43]

Done.

+  EXPECT_EQ(0, GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsTime")->TotalCount());
+
+  // No longer concurrent.
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart("Media.Audible.ConcurrentTabsTime"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(1000));
+  }
+
+  // Stopping the second tab is a no-op.
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, false);
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart("Media.Audible.ConcurrentTabsTime"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(1000));
+  }
+}
+
+TEST_F(AudibleMetricsTest, ConcurrentTabsTimeRunsAsLongAsTwoAudibleTabs) {
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, true);
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, true);
+
+  clock()->Advance(base::TimeDelta::FromMilliseconds(1000));
+
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_2, true);
+
+  clock()->Advance(base::TimeDelta::FromMilliseconds(500));
+
+  // Mutes one of the three audible tabs.
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_1, false);
+
+  // No record because concurrent audbile tabs still running.
+  EXPECT_EQ(0, GetHistogramSamplesSinceTestStart(
+      "Media.Audible.ConcurrentTabsTime")->TotalCount());
+
+  // Mutes the first audible tab.
+  audible_metrics().UpdateAudibleWebContentsState(WEB_CONTENTS_0, false);
+  {
+    scoped_ptr<base::HistogramSamples> samples(
+        GetHistogramSamplesSinceTestStart("Media.Audible.ConcurrentTabsTime"));
+    EXPECT_EQ(1, samples->TotalCount());
+    EXPECT_EQ(1, samples->GetCount(1500));
+  }
+}
+
+}  // namespace content