Report histogram creation results.

base/metrics/histogram_base_unittest.cc

Index: base/metrics/histogram_base_unittest.cc
diff --git a/base/metrics/histogram_base_unittest.cc b/base/metrics/histogram_base_unittest.cc
index 2d6b6df0288850cab31362762957070201ca72e3..6b41597b4a10a489b35bbf10c92d73fc1a4962cb 100644
--- a/base/metrics/histogram_base_unittest.cc
+++ b/base/metrics/histogram_base_unittest.cc
@@ -18,19 +18,29 @@ class HistogramBaseTest : public testing::Test {
   HistogramBaseTest() {
     // Each test will have a clean state (no Histogram / BucketRanges
     // registered).
-    statistics_recorder_ = NULL;
     ResetStatisticsRecorder();
   }
 
-  ~HistogramBaseTest() override { delete statistics_recorder_; }
+  ~HistogramBaseTest() override {
+    HistogramBase::report_histogram_ = nullptr;
+  }
 
   void ResetStatisticsRecorder() {
-    delete statistics_recorder_;
-    statistics_recorder_ = new StatisticsRecorder();
+    // It is necessary to fully destruct any existing StatisticsRecorder
+    // before creating a new one.
+    statistics_recorder_.reset();
+    statistics_recorder_.reset(new StatisticsRecorder());
+  }
+
+  HistogramBase* GetCreationReportHistogram(const std::string& name) {
+    HistogramBase::EnableActivityReportHistogram(name);
+    return HistogramBase::report_histogram_;
   }
 
  private:
-  StatisticsRecorder* statistics_recorder_;
+  scoped_ptr<StatisticsRecorder> statistics_recorder_;
+
+  DISALLOW_COPY_AND_ASSIGN(HistogramBaseTest);
 };
 
 TEST_F(HistogramBaseTest, DeserializeHistogram) {
@@ -152,4 +162,61 @@ TEST_F(HistogramBaseTest, DeserializeSparseHistogram) {
   EXPECT_EQ(0, deserialized->flags());
 }
 
+TEST_F(HistogramBaseTest, CreationReportHistogram) {
+  // Enabled creation report. Itself is not included in the report.
+  HistogramBase* report = GetCreationReportHistogram("CreationReportTest");
+  ASSERT_TRUE(report);
+
+  std::vector<HistogramBase::Sample> ranges;
+  ranges.push_back(1);
+  ranges.push_back(2);
+  ranges.push_back(4);
+  ranges.push_back(8);
+  ranges.push_back(10);
+
+  // Create all histogram types and verify counts.
+  Histogram::FactoryGet("CRH-Histogram", 1, 10, 5, 0);
+  LinearHistogram::FactoryGet("CRH-Linear", 1, 10, 5, 0);
+  BooleanHistogram::FactoryGet("CRH-Boolean", 0);
+  CustomHistogram::FactoryGet("CRH-Custom", ranges, 0);
+  SparseHistogram::FactoryGet("CRH-Sparse", 0);
+
+  scoped_ptr<HistogramSamples> samples = report->SnapshotSamples();
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_CREATED));
+  EXPECT_EQ(5, samples->GetCount(HISTOGRAM_REPORT_HISTOGRAM_CREATED));
+  EXPECT_EQ(0, samples->GetCount(HISTOGRAM_REPORT_HISTOGRAM_LOOKUP));
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_TYPE_LOGARITHMIC));
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_TYPE_LINEAR));
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_TYPE_BOOLEAN));
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_TYPE_CUSTOM));
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_TYPE_SPARSE));
+
+  // Create all flag types and verify counts.
+  Histogram::FactoryGet("CRH-Histogram-UMA-Targeted", 1, 10, 5,
+                        HistogramBase::kUmaTargetedHistogramFlag);
+  Histogram::FactoryGet("CRH-Histogram-UMA-Stability", 1, 10, 5,
+                        HistogramBase::kUmaStabilityHistogramFlag);
+  SparseHistogram::FactoryGet("CRH-Sparse-UMA-Targeted",
+                              HistogramBase::kUmaTargetedHistogramFlag);
+  SparseHistogram::FactoryGet("CRH-Sparse-UMA-Stability",
+                              HistogramBase::kUmaStabilityHistogramFlag);
+  samples = report->SnapshotSamples();
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_CREATED));
+  EXPECT_EQ(9, samples->GetCount(HISTOGRAM_REPORT_HISTOGRAM_CREATED));
+  EXPECT_EQ(0, samples->GetCount(HISTOGRAM_REPORT_HISTOGRAM_LOOKUP));
+  EXPECT_EQ(2, samples->GetCount(HISTOGRAM_REPORT_FLAG_UMA_TARGETED));
+  EXPECT_EQ(2, samples->GetCount(HISTOGRAM_REPORT_FLAG_UMA_STABILITY));
+
+  // Do lookup of existing histograms and verify counts.
+  Histogram::FactoryGet("CRH-Histogram", 1, 10, 5, 0);
+  LinearHistogram::FactoryGet("CRH-Linear", 1, 10, 5, 0);
+  BooleanHistogram::FactoryGet("CRH-Boolean", 0);
+  CustomHistogram::FactoryGet("CRH-Custom", ranges, 0);
+  SparseHistogram::FactoryGet("CRH-Sparse", 0);
+  samples = report->SnapshotSamples();
+  EXPECT_EQ(1, samples->GetCount(HISTOGRAM_REPORT_CREATED));
+  EXPECT_EQ(9, samples->GetCount(HISTOGRAM_REPORT_HISTOGRAM_CREATED));
+  EXPECT_EQ(5, samples->GetCount(HISTOGRAM_REPORT_HISTOGRAM_LOOKUP));
+}
+
 }  // namespace base