1 // Copyright 2013 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/histogram_delta_serialization.h" 6 7 #include <vector> 8 9 #include "base/metrics/histogram.h" 10 #include "base/metrics/histogram_base.h" 11 #include "base/metrics/statistics_recorder.h" 12 #include "testing/gtest/include/gtest/gtest.h" 13 14 namespace base { 15 16 TEST(HistogramDeltaSerializationTest, DeserializeHistogramAndAddSamples) { 17 std::unique_ptr<StatisticsRecorder> statistic_recorder( 18 StatisticsRecorder::CreateTemporaryForTesting()); 19 HistogramDeltaSerialization serializer("HistogramDeltaSerializationTest"); 20 std::vector<std::string> deltas; 21 // Nothing was changed yet. 22 serializer.PrepareAndSerializeDeltas(&deltas, true); 23 EXPECT_TRUE(deltas.empty()); 24 25 HistogramBase* histogram = Histogram::FactoryGet( 26 "TestHistogram", 1, 1000, 10, HistogramBase::kIPCSerializationSourceFlag); 27 histogram->Add(1); 28 histogram->Add(10); 29 histogram->Add(100); 30 histogram->Add(1000); 31 32 serializer.PrepareAndSerializeDeltas(&deltas, true); 33 EXPECT_FALSE(deltas.empty()); 34 35 HistogramDeltaSerialization::DeserializeAndAddSamples(deltas); 36 37 // The histogram has kIPCSerializationSourceFlag. So samples will be ignored. 38 std::unique_ptr<HistogramSamples> snapshot(histogram->SnapshotSamples()); 39 EXPECT_EQ(1, snapshot->GetCount(1)); 40 EXPECT_EQ(1, snapshot->GetCount(10)); 41 EXPECT_EQ(1, snapshot->GetCount(100)); 42 EXPECT_EQ(1, snapshot->GetCount(1000)); 43 44 // Clear kIPCSerializationSourceFlag to emulate multi-process usage. 45 histogram->ClearFlags(HistogramBase::kIPCSerializationSourceFlag); 46 HistogramDeltaSerialization::DeserializeAndAddSamples(deltas); 47 48 std::unique_ptr<HistogramSamples> snapshot2(histogram->SnapshotSamples()); 49 EXPECT_EQ(2, snapshot2->GetCount(1)); 50 EXPECT_EQ(2, snapshot2->GetCount(10)); 51 EXPECT_EQ(2, snapshot2->GetCount(100)); 52 EXPECT_EQ(2, snapshot2->GetCount(1000)); 53 } 54 55 } // namespace base 56
