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base / test / metrics / histogram_tester_unittest.cc [blame]
// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/test/metrics/histogram_tester.h"
#include <memory>
#include <string>
#include "base/metrics/histogram_macros.h"
#include "base/metrics/histogram_samples.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest-spi.h"
#include "testing/gtest/include/gtest/gtest.h"
using ::testing::ElementsAre;
using ::testing::IsEmpty;
namespace {
const char kHistogram1[] = "Test1";
const char kHistogram2[] = "Test2";
const char kHistogram3[] = "Test3";
const char kHistogram4[] = "Test4";
const char kHistogram5[] = "Test5";
const char kHistogram6[] = "Test6";
} // namespace
namespace base {
typedef testing::Test HistogramTesterTest;
TEST_F(HistogramTesterTest, Scope) {
// Record a histogram before the creation of the recorder.
UMA_HISTOGRAM_BOOLEAN(kHistogram1, true);
HistogramTester tester;
// Verify that no histogram is recorded.
tester.ExpectTotalCount(kHistogram1, 0);
// Record a histogram after the creation of the recorder.
UMA_HISTOGRAM_BOOLEAN(kHistogram1, true);
// Verify that one histogram is recorded.
std::unique_ptr<HistogramSamples> samples(
tester.GetHistogramSamplesSinceCreation(kHistogram1));
EXPECT_TRUE(samples);
EXPECT_EQ(1, samples->TotalCount());
}
TEST_F(HistogramTesterTest, GetHistogramSamplesSinceCreationNotNull) {
// Chose the histogram name uniquely, to ensure nothing was recorded for it so
// far.
static const char kHistogram[] =
"GetHistogramSamplesSinceCreationNotNullHistogram";
HistogramTester tester;
// Verify that the returned samples are empty but not null.
std::unique_ptr<HistogramSamples> samples(
tester.GetHistogramSamplesSinceCreation(kHistogram1));
EXPECT_TRUE(samples);
tester.ExpectTotalCount(kHistogram, 0);
}
TEST_F(HistogramTesterTest, TestUniqueSample) {
HistogramTester tester;
// Emit '2' three times.
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
tester.ExpectUniqueSample(kHistogram2, 2, 3);
tester.ExpectUniqueTimeSample(kHistogram2, base::Milliseconds(2), 3);
}
// Verify that the expectation is violated if the bucket contains an incorrect
// number of samples.
TEST_F(HistogramTesterTest, TestUniqueSample_TooManySamplesInActualBucket) {
auto failing_code = [] {
HistogramTester tester;
// Emit '2' four times.
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
// Expect exactly three samples in bucket 2. This is supposed to fail.
tester.ExpectUniqueSample(kHistogram2, 2, 3);
};
EXPECT_NONFATAL_FAILURE(failing_code(),
"Histogram \"Test2\" did not meet its expectations.");
}
// Verify that the expectation is violated if the bucket contains the correct
// number of samples but another bucket contains extra samples.
TEST_F(HistogramTesterTest, TestUniqueSample_OneExtraSampleInWrongBucket) {
auto failing_code = [] {
HistogramTester tester;
// Emit '2' three times.
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 2);
// Emit one unexpected '3'.
UMA_HISTOGRAM_COUNTS_100(kHistogram2, 3);
// Expect exactly three samples in bucket 2. This is supposed to fail.
tester.ExpectUniqueSample(kHistogram2, 2, 3);
};
EXPECT_NONFATAL_FAILURE(failing_code(),
"Histogram \"Test2\" did not meet its expectations.");
}
TEST_F(HistogramTesterTest, TestBucketsSample) {
HistogramTester tester;
UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram3, 2);
UMA_HISTOGRAM_COUNTS_100(kHistogram3, 3);
tester.ExpectBucketCount(kHistogram3, 2, 4);
tester.ExpectBucketCount(kHistogram3, 3, 1);
tester.ExpectTotalCount(kHistogram3, 5);
}
TEST_F(HistogramTesterTest, TestBucketsSampleWithScope) {
// Emit values twice, once before the tester creation and once after.
UMA_HISTOGRAM_COUNTS_100(kHistogram4, 2);
HistogramTester tester;
UMA_HISTOGRAM_COUNTS_100(kHistogram4, 3);
tester.ExpectBucketCount(kHistogram4, 2, 0);
tester.ExpectBucketCount(kHistogram4, 3, 1);
tester.ExpectTotalCount(kHistogram4, 1);
}
TEST_F(HistogramTesterTest, TestGetAllSamples) {
HistogramTester tester;
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 2, 5);
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 3, 5);
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 3, 5);
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 5, 5);
EXPECT_THAT(tester.GetAllSamples(kHistogram5),
ElementsAre(Bucket(2, 1), Bucket(3, 2), Bucket(5, 1)));
}
TEST_F(HistogramTesterTest, TestGetAllSamples_NoSamples) {
HistogramTester tester;
EXPECT_THAT(tester.GetAllSamples(kHistogram5), IsEmpty());
}
TEST_F(HistogramTesterTest, TestGetTotalSum) {
// Emit values twice, once before the tester creation and once after.
UMA_HISTOGRAM_COUNTS_100(kHistogram4, 2);
HistogramTester tester;
UMA_HISTOGRAM_COUNTS_100(kHistogram4, 3);
UMA_HISTOGRAM_COUNTS_100(kHistogram4, 4);
EXPECT_EQ(7, tester.GetTotalSum(kHistogram4));
}
TEST_F(HistogramTesterTest, TestGetTotalCountsForPrefix) {
HistogramTester tester;
UMA_HISTOGRAM_ENUMERATION("Test1.Test2.Test3", 2, 5);
// Regression check for bug https://crbug.com/659977.
EXPECT_TRUE(tester.GetTotalCountsForPrefix("Test2.").empty());
EXPECT_EQ(1u, tester.GetTotalCountsForPrefix("Test1.").size());
}
TEST_F(HistogramTesterTest, TestGetAllChangedHistograms) {
// Emit multiple values, some before tester creation.
UMA_HISTOGRAM_COUNTS_100(kHistogram6, true);
UMA_HISTOGRAM_COUNTS_100(kHistogram4, 4);
HistogramTester tester;
UMA_HISTOGRAM_COUNTS_100(kHistogram4, 3);
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 2, 5);
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 3, 5);
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 4, 5);
UMA_HISTOGRAM_ENUMERATION(kHistogram5, 5, 5);
UMA_HISTOGRAM_ENUMERATION("Test1.Test2.Test3", 2, 5);
std::string results = tester.GetAllHistogramsRecorded();
EXPECT_EQ(std::string::npos, results.find("Histogram: Test1 recorded"));
EXPECT_NE(std::string::npos,
results.find("Histogram: Test4 recorded 1 new samples"));
EXPECT_NE(std::string::npos,
results.find("Histogram: Test5 recorded 4 new samples"));
EXPECT_NE(
std::string::npos,
results.find("Histogram: Test1.Test2.Test3 recorded 1 new samples"));
}
TEST_F(HistogramTesterTest, MissingHistogramMeansEmptyBuckets) {
// When a histogram hasn't been instantiated, expecting counts of zero should
// still succeed.
static const char kHistogram[] = "MissingHistogramMeansEmptyBucketsHistogram";
HistogramTester tester;
tester.ExpectBucketCount(kHistogram, 42, 0);
tester.ExpectTotalCount(kHistogram, 0);
EXPECT_TRUE(tester.GetAllSamples(kHistogram).empty());
EXPECT_EQ(0, tester.GetTotalSum(kHistogram));
EXPECT_EQ(0, tester.GetBucketCount(kHistogram, 42));
EXPECT_EQ(0,
tester.GetHistogramSamplesSinceCreation(kHistogram)->TotalCount());
}
TEST_F(HistogramTesterTest, BucketsAre) {
// Auxiliary functions for keeping the lines short.
auto a = [](std::vector<Bucket> b) { return b; };
auto b = [](base::Histogram::Sample min, base::Histogram::Count count) {
return Bucket(min, count);
};
using ::testing::Not;
EXPECT_THAT(a({}), BucketsAre());
EXPECT_THAT(a({}), BucketsAre(b(0, 0)));
EXPECT_THAT(a({}), BucketsAre(b(1, 0)));
EXPECT_THAT(a({}), BucketsAre(b(0, 0), b(1, 0)));
EXPECT_THAT(a({}), Not(BucketsAre(b(1, 1))));
EXPECT_THAT(a({b(1, 1)}), BucketsAre(b(1, 1)));
EXPECT_THAT(a({b(1, 1)}), BucketsAre(b(0, 0), b(1, 1)));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre()));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre(b(0, 0))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre(b(1, 0))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre(b(2, 1))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre(b(2, 2))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre(b(0, 0), b(1, 0))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre(b(0, 0), b(1, 1), b(2, 2))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsAre(b(0, 0), b(1, 0), b(2, 0))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsAre(b(1, 1), b(2, 2)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsAre(b(0, 0), b(1, 1), b(2, 2)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre()));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre(b(0, 0))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre(b(1, 1))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre(b(2, 2))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre(b(0, 0), b(1, 1))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre(b(1, 0))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre(b(2, 1))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsAre(b(0, 0), b(1, 0))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}),
Not(BucketsAre(b(0, 0), b(1, 0), b(2, 0))));
}
TEST_F(HistogramTesterTest, BucketsInclude) {
// Auxiliary function for the "actual" values to shorten lines.
auto a = [](std::vector<Bucket> b) { return b; };
auto b = [](base::Histogram::Sample min, base::Histogram::Count count) {
return Bucket(min, count);
};
using ::testing::Not;
EXPECT_THAT(a({}), BucketsInclude());
EXPECT_THAT(a({}), BucketsInclude(b(0, 0)));
EXPECT_THAT(a({}), BucketsInclude(b(1, 0)));
EXPECT_THAT(a({}), BucketsInclude(b(0, 0), b(1, 0)));
EXPECT_THAT(a({}), Not(BucketsInclude(b(1, 1))));
EXPECT_THAT(a({b(1, 1)}), BucketsInclude());
EXPECT_THAT(a({b(1, 1)}), BucketsInclude(b(0, 0)));
EXPECT_THAT(a({b(1, 1)}), BucketsInclude(b(1, 1)));
EXPECT_THAT(a({b(1, 1)}), BucketsInclude(b(0, 0), b(1, 1)));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsInclude(b(1, 0))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsInclude(b(2, 1))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsInclude(b(2, 2))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsInclude(b(0, 0), b(1, 0))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsInclude(b(0, 0), b(1, 1), b(2, 2))));
EXPECT_THAT(a({b(1, 1)}), Not(BucketsInclude(b(0, 0), b(1, 0), b(2, 0))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsInclude());
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsInclude(b(0, 0)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsInclude(b(1, 1)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsInclude(b(2, 2)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsInclude(b(0, 0), b(1, 1)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsInclude(b(1, 1), b(2, 2)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), BucketsInclude(b(0, 0), b(1, 1), b(2, 2)));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsInclude(b(1, 0))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsInclude(b(2, 1))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}), Not(BucketsInclude(b(0, 0), b(1, 0))));
EXPECT_THAT(a({b(1, 1), b(2, 2)}),
Not(BucketsInclude(b(0, 0), b(1, 0), b(2, 0))));
}
} // namespace base