1 // Copyright 2017 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/metrics/single_sample_metrics.h"
6
7 #include "base/memory/ptr_util.h"
8 #include "base/metrics/dummy_histogram.h"
9 #include "base/test/gtest_util.h"
10 #include "base/test/metrics/histogram_tester.h"
11 #include "testing/gtest/include/gtest/gtest.h"
12
13 namespace base {
14
15 namespace {
16
17 const HistogramBase::Sample kMin = 1;
18 const HistogramBase::Sample kMax = 10;
19 const uint32_t kBucketCount = 10;
20 const char kMetricName[] = "Single.Sample.Metric";
21
22 class SingleSampleMetricsTest : public testing::Test {
23 public:
24 SingleSampleMetricsTest() = default;
25
~SingleSampleMetricsTest()26 ~SingleSampleMetricsTest() override {
27 // Ensure we cleanup after ourselves.
28 SingleSampleMetricsFactory::DeleteFactoryForTesting();
29 }
30
31 private:
32 DISALLOW_COPY_AND_ASSIGN(SingleSampleMetricsTest);
33 };
34
35 } // namespace
36
TEST_F(SingleSampleMetricsTest,DefaultFactoryGetSet)37 TEST_F(SingleSampleMetricsTest, DefaultFactoryGetSet) {
38 SingleSampleMetricsFactory* factory = SingleSampleMetricsFactory::Get();
39 ASSERT_TRUE(factory);
40
41 // Same factory should be returned evermore.
42 EXPECT_EQ(factory, SingleSampleMetricsFactory::Get());
43
44 // Setting a factory after the default has been instantiated should fail.
45 EXPECT_DCHECK_DEATH(SingleSampleMetricsFactory::SetFactory(
46 WrapUnique<SingleSampleMetricsFactory>(nullptr)));
47 }
48
TEST_F(SingleSampleMetricsTest,CustomFactoryGetSet)49 TEST_F(SingleSampleMetricsTest, CustomFactoryGetSet) {
50 SingleSampleMetricsFactory* factory = new DefaultSingleSampleMetricsFactory();
51 SingleSampleMetricsFactory::SetFactory(WrapUnique(factory));
52 EXPECT_EQ(factory, SingleSampleMetricsFactory::Get());
53 }
54
TEST_F(SingleSampleMetricsTest,DefaultSingleSampleMetricNoValue)55 TEST_F(SingleSampleMetricsTest, DefaultSingleSampleMetricNoValue) {
56 SingleSampleMetricsFactory* factory = SingleSampleMetricsFactory::Get();
57
58 HistogramTester tester;
59 std::unique_ptr<SingleSampleMetric> metric =
60 factory->CreateCustomCountsMetric(kMetricName, kMin, kMax, kBucketCount);
61 metric.reset();
62
63 // Verify that no sample is recorded if SetSample() is never called.
64 tester.ExpectTotalCount(kMetricName, 0);
65 }
66
TEST_F(SingleSampleMetricsTest,DefaultSingleSampleMetricWithValue)67 TEST_F(SingleSampleMetricsTest, DefaultSingleSampleMetricWithValue) {
68 SingleSampleMetricsFactory* factory = SingleSampleMetricsFactory::Get();
69
70 HistogramTester tester;
71 std::unique_ptr<SingleSampleMetric> metric =
72 factory->CreateCustomCountsMetric(kMetricName, kMin, kMax, kBucketCount);
73
74 const HistogramBase::Sample kLastSample = 9;
75 metric->SetSample(1);
76 metric->SetSample(3);
77 metric->SetSample(5);
78 metric->SetSample(kLastSample);
79 metric.reset();
80
81 // Verify only the last sample sent to SetSample() is recorded.
82 tester.ExpectUniqueSample(kMetricName, kLastSample, 1);
83
84 // Verify construction implicitly by requesting a histogram with the same
85 // parameters; this test relies on the fact that histogram objects are unique
86 // per name. Different parameters will result in a Dummy histogram returned.
87 EXPECT_EQ(
88 DummyHistogram::GetInstance(),
89 Histogram::FactoryGet(kMetricName, 1, 3, 3, HistogramBase::kNoFlags));
90 EXPECT_NE(DummyHistogram::GetInstance(),
91 Histogram::FactoryGet(kMetricName, kMin, kMax, kBucketCount,
92 HistogramBase::kUmaTargetedHistogramFlag));
93 }
94
TEST_F(SingleSampleMetricsTest,MultipleMetricsAreDistinct)95 TEST_F(SingleSampleMetricsTest, MultipleMetricsAreDistinct) {
96 SingleSampleMetricsFactory* factory = SingleSampleMetricsFactory::Get();
97
98 HistogramTester tester;
99 std::unique_ptr<SingleSampleMetric> metric =
100 factory->CreateCustomCountsMetric(kMetricName, kMin, kMax, kBucketCount);
101 std::unique_ptr<SingleSampleMetric> metric2 =
102 factory->CreateCustomCountsMetric(kMetricName, kMin, kMax, kBucketCount);
103 const char kMetricName2[] = "Single.Sample.Metric.2";
104 std::unique_ptr<SingleSampleMetric> metric3 =
105 factory->CreateCustomCountsMetric(kMetricName2, kMin, kMax, kBucketCount);
106
107 const HistogramBase::Sample kSample1 = 5;
108 metric->SetSample(kSample1);
109 metric2->SetSample(kSample1);
110
111 const HistogramBase::Sample kSample2 = 7;
112 metric3->SetSample(kSample2);
113
114 metric.reset();
115 tester.ExpectUniqueSample(kMetricName, kSample1, 1);
116
117 metric2.reset();
118 tester.ExpectUniqueSample(kMetricName, kSample1, 2);
119
120 metric3.reset();
121 tester.ExpectUniqueSample(kMetricName2, kSample2, 1);
122 }
123
124 } // namespace base
125