base/test/histogram_tester_unittest.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/test/histogram_tester.h"
   6
   7 #include "base/memory/scoped_ptr.h"
   8 #include "base/metrics/histogram_macros.h"
   9 #include "base/metrics/histogram_samples.h"
  10 #include "testing/gmock/include/gmock/gmock.h"
  11 #include "testing/gtest/include/gtest/gtest.h"
  12
  13 using ::testing::ElementsAre;
  14 using ::testing::IsEmpty;
  15
  16 namespace {
  17
  18 const char kHistogram1[] = "Test1";
  19 const char kHistogram2[] = "Test2";
  20 const char kHistogram3[] = "Test3";
  21 const char kHistogram4[] = "Test4";
  22 const char kHistogram5[] = "Test5";
  23
  24 }  // namespace
  25
  26 namespace base {
  27
  28 typedef testing::Test HistogramTesterTest;
  29
  30 TEST_F(HistogramTesterTest, Scope) {
  31   // Record a histogram before the creation of the recorder.
  32   UMA_HISTOGRAM_BOOLEAN(kHistogram1, true);
  33
  34   HistogramTester tester;
  35
  36   // Verify that no histogram is recorded.
  37   tester.ExpectTotalCount(kHistogram1, 0);
  38
  39   // Record a histogram after the creation of the recorder.
  40   UMA_HISTOGRAM_BOOLEAN(kHistogram1, true);
  41
  42   // Verify that one histogram is recorded.
  43   scoped_ptr<HistogramSamples> samples(
  44       tester.GetHistogramSamplesSinceCreation(kHistogram1));
  45   EXPECT_TRUE(samples);
  46   EXPECT_EQ(1, samples->TotalCount());
  47 }
  48
  49 TEST_F(HistogramTesterTest, GetHistogramSamplesSinceCreationNotNull) {
  50   // Chose the histogram name uniquely, to ensure nothing was recorded for it so
  51   // far.
  52   static const char kHistogram[] =
  53       "GetHistogramSamplesSinceCreationNotNullHistogram";
  54   HistogramTester tester;
  55
  56   // Verify that the returned samples are empty but not null.
  57   scoped_ptr<HistogramSamples> samples(
  58       tester.GetHistogramSamplesSinceCreation(kHistogram1));
  59   EXPECT_TRUE(samples);
  60   tester.ExpectTotalCount(kHistogram, 0);
  61 }
  62
  63 TEST_F(HistogramTesterTest, TestUniqueSample) {
  64   HistogramTester tester;
  65
  66   // Record into a sample thrice
  67   UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
  68   UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
  69   UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
  70
  71   tester.ExpectUniqueSample(kHistogram2, 2, 3);
  72 }
  73
  74 TEST_F(HistogramTesterTest, TestBucketsSample) {
  75   HistogramTester tester;
  76
  77   // Record into a sample twice
  78   UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
  79   UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
  80   UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
  81   UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
  82   UMA_HISTOGRAM_COUNTS_100(kHistogram3, 3);
  83
  84   tester.ExpectBucketCount(kHistogram3, 2, 4);
  85   tester.ExpectBucketCount(kHistogram3, 3, 1);
  86
  87   tester.ExpectTotalCount(kHistogram3, 5);
  88 }
  89
  90 TEST_F(HistogramTesterTest, TestBucketsSampleWithScope) {
  91   // Record into a sample twice, once before the tester creation and once after.
  92   UMA_HISTOGRAM_COUNTS_100(kHistogram4, 2);
  93
  94   HistogramTester tester;
  95   UMA_HISTOGRAM_COUNTS_100(kHistogram4, 3);
  96
  97   tester.ExpectBucketCount(kHistogram4, 2, 0);
  98   tester.ExpectBucketCount(kHistogram4, 3, 1);
  99
 100   tester.ExpectTotalCount(kHistogram4, 1);
 101 }
 102
 103 TEST_F(HistogramTesterTest, TestGetAllSamples) {
 104   HistogramTester tester;
 105   UMA_HISTOGRAM_ENUMERATION(kHistogram5, 2, 5);
 106   UMA_HISTOGRAM_ENUMERATION(kHistogram5, 3, 5);
 107   UMA_HISTOGRAM_ENUMERATION(kHistogram5, 3, 5);
 108   UMA_HISTOGRAM_ENUMERATION(kHistogram5, 5, 5);
 109
 110   EXPECT_THAT(tester.GetAllSamples(kHistogram5),
 111               ElementsAre(Bucket(2, 1), Bucket(3, 2), Bucket(5, 1)));
 112 }
 113
 114 TEST_F(HistogramTesterTest, TestGetAllSamples_NoSamples) {
 115   HistogramTester tester;
 116   EXPECT_THAT(tester.GetAllSamples(kHistogram5), IsEmpty());
 117 }
 118
 119 }  // namespace base