1 // Copyright (c) 2012 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 "chrome/test/base/uma_histogram_helper.h" 6 7 #include "base/bind.h" 8 #include "base/metrics/statistics_recorder.h" 9 #include "base/test/test_timeouts.h" 10 #include "chrome/test/base/ui_test_utils.h" 11 #include "content/public/browser/histogram_fetcher.h" 12 13 UMAHistogramHelper::UMAHistogramHelper() { 14 base::StatisticsRecorder::Initialize(); 15 } 16 17 UMAHistogramHelper::~UMAHistogramHelper() { 18 } 19 20 void UMAHistogramHelper::PrepareSnapshot(const char* const histogram_names[], 21 size_t num_histograms) { 22 for (size_t i = 0; i < num_histograms; ++i) { 23 std::string histogram_name = histogram_names[i]; 24 25 base::HistogramBase* histogram = 26 base::StatisticsRecorder::FindHistogram(histogram_name); 27 // If there is no histogram present, then don't record a snapshot. The logic 28 // in the Expect* methods will act to treat no histogram equivalent to 29 // samples with zeros. 30 if (histogram) { 31 histogram_snapshots[histogram_name] = 32 make_linked_ptr(histogram->SnapshotSamples().release()); 33 } 34 } 35 } 36 37 void UMAHistogramHelper::Fetch() { 38 base::Closure callback = base::Bind(&UMAHistogramHelper::FetchCallback, 39 base::Unretained(this)); 40 41 content::FetchHistogramsAsynchronously( 42 base::MessageLoop::current(), 43 callback, 44 // If this call times out, it means that a child process is not 45 // responding, which is something we should not ignore. The timeout is 46 // set to be longer than the normal browser test timeout so that it will 47 // be prempted by the normal timeout. 48 TestTimeouts::action_max_timeout() * 2); 49 content::RunMessageLoop(); 50 } 51 52 void UMAHistogramHelper::ExpectUniqueSample( 53 const std::string& name, 54 base::HistogramBase::Sample sample, 55 base::HistogramBase::Count expected_count) { 56 base::HistogramBase* histogram = 57 base::StatisticsRecorder::FindHistogram(name); 58 EXPECT_NE(static_cast<base::HistogramBase*>(NULL), histogram) 59 << "Histogram \"" << name << "\" does not exist."; 60 61 if (histogram) { 62 scoped_ptr<base::HistogramSamples> samples(histogram->SnapshotSamples()); 63 CheckBucketCount(name, sample, expected_count, *samples); 64 CheckTotalCount(name, expected_count, *samples); 65 } 66 } 67 68 void UMAHistogramHelper::ExpectBucketCount( 69 const std::string& name, 70 base::HistogramBase::Sample sample, 71 base::HistogramBase::Count expected_count) { 72 base::HistogramBase* histogram = 73 base::StatisticsRecorder::FindHistogram(name); 74 EXPECT_NE(static_cast<base::HistogramBase*>(NULL), histogram) 75 << "Histogram \"" << name << "\" does not exist."; 76 77 if (histogram) { 78 scoped_ptr<base::HistogramSamples> samples(histogram->SnapshotSamples()); 79 CheckBucketCount(name, sample, expected_count, *samples); 80 } 81 } 82 83 void UMAHistogramHelper::ExpectTotalCount( 84 const std::string& name, 85 base::HistogramBase::Count count) { 86 base::HistogramBase* histogram = 87 base::StatisticsRecorder::FindHistogram(name); 88 if (histogram) { 89 scoped_ptr<base::HistogramSamples> samples(histogram->SnapshotSamples()); 90 CheckTotalCount(name, count, *samples); 91 } else { 92 // No histogram means there were zero samples. 93 EXPECT_EQ(count, 0) << "Histogram \"" << name << "\" does not exist."; 94 } 95 } 96 97 void UMAHistogramHelper::FetchCallback() { 98 base::MessageLoopForUI::current()->Quit(); 99 } 100 101 void UMAHistogramHelper::CheckBucketCount( 102 const std::string& name, 103 base::HistogramBase::Sample sample, 104 base::HistogramBase::Count expected_count, 105 base::HistogramSamples& samples) { 106 int actual_count = samples.GetCount(sample); 107 if (histogram_snapshots.count(name)) 108 actual_count -= histogram_snapshots[name]->GetCount(sample); 109 EXPECT_EQ(expected_count, actual_count) 110 << "Histogram \"" << name 111 << "\" does not have the right number of samples (" << expected_count 112 << ") in the expected bucket (" << sample << "). It has (" << actual_count 113 << ")."; 114 } 115 116 void UMAHistogramHelper::CheckTotalCount( 117 const std::string& name, 118 base::HistogramBase::Count expected_count, 119 base::HistogramSamples& samples) { 120 int actual_count = samples.TotalCount(); 121 if (histogram_snapshots.count(name)) 122 actual_count -= histogram_snapshots[name]->TotalCount(); 123 EXPECT_EQ(expected_count, actual_count) 124 << "Histogram \"" << name 125 << "\" does not have the right total number of samples (" 126 << expected_count << "). It has (" << actual_count << ")."; 127 } 128