Support negative sample values in PersistentHistogramMap.

base/metrics/persistent_sample_map_unittest.cc

 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/metrics/persistent_sample_map.h"
 
 #include <memory>
 
 #include "base/metrics/persistent_histogram_allocator.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
-namespace {
 
 TEST(PersistentSampleMapTest, AccumulateTest) {
   LocalPersistentMemoryAllocator allocator(64 << 10, 0, "");  // 64 KiB
 
   HistogramSamples::Metadata meta;
   PersistentSparseHistogramDataManager manager(&allocator);
   PersistentSampleMap samples(1, &manager, &meta);
 
   samples.Accumulate(1, 100);
   samples.Accumulate(2, 200);
@@ skipping 54 matching lines @@
   EXPECT_EQ(100, samples1.GetCount(1));
   EXPECT_EQ(100, samples1.GetCount(2));
   EXPECT_EQ(100, samples1.GetCount(3));
   EXPECT_EQ(0, samples1.GetCount(4));
   EXPECT_EQ(600, samples1.sum());
   EXPECT_EQ(300, samples1.TotalCount());
   EXPECT_EQ(samples1.redundant_count(), samples1.TotalCount());
 }
 
 TEST(PersistentSampleMapTest, PersistenceTest) {
+  const int kAllSamples = PersistentSampleMap::kAllSamples;
+
   LocalPersistentMemoryAllocator allocator(64 << 10, 0, "");  // 64 KiB
 
   HistogramSamples::Metadata meta12;
   PersistentSparseHistogramDataManager manager1(&allocator);
   PersistentSampleMap samples1(12, &manager1, &meta12);
   samples1.Accumulate(1, 100);
   samples1.Accumulate(2, 200);
   samples1.Accumulate(1, -200);
+  samples1.Accumulate(kAllSamples, 1);
   EXPECT_EQ(-100, samples1.GetCount(1));
   EXPECT_EQ(200, samples1.GetCount(2));
-  EXPECT_EQ(300, samples1.sum());
-  EXPECT_EQ(100, samples1.TotalCount());
+  EXPECT_EQ(1, samples1.GetCount(kAllSamples));
+  EXPECT_EQ(300 + kAllSamples, samples1.sum());
+  EXPECT_EQ(101, samples1.TotalCount());
   EXPECT_EQ(samples1.redundant_count(), samples1.TotalCount());
 
   PersistentSparseHistogramDataManager manager2(&allocator);
   PersistentSampleMap samples2(12, &manager2, &meta12);
   EXPECT_EQ(samples1.id(), samples2.id());
   EXPECT_EQ(samples1.sum(), samples2.sum());
   EXPECT_EQ(samples1.redundant_count(), samples2.redundant_count());
   EXPECT_EQ(samples1.TotalCount(), samples2.TotalCount());
   EXPECT_EQ(-100, samples2.GetCount(1));
   EXPECT_EQ(200, samples2.GetCount(2));
-  EXPECT_EQ(300, samples2.sum());
-  EXPECT_EQ(100, samples2.TotalCount());
+  EXPECT_EQ(1, samples2.GetCount(kAllSamples));
+  EXPECT_EQ(300 + kAllSamples, samples2.sum());
+  EXPECT_EQ(101, samples2.TotalCount());
   EXPECT_EQ(samples2.redundant_count(), samples2.TotalCount());
 
+  samples1.Accumulate(kAllSamples, -1);
   EXPECT_EQ(0, samples2.GetCount(3));
   EXPECT_EQ(0, samples1.GetCount(3));
   samples2.Accumulate(3, 300);
   EXPECT_EQ(300, samples2.GetCount(3));
   EXPECT_EQ(300, samples1.GetCount(3));
   EXPECT_EQ(samples1.sum(), samples2.sum());
   EXPECT_EQ(samples1.redundant_count(), samples2.redundant_count());
   EXPECT_EQ(samples1.TotalCount(), samples2.TotalCount());
 
   EXPECT_EQ(0, samples2.GetCount(4));
@@ skipping 113 matching lines @@
 
   EXPECT_DEATH(it->Next(), "");
 
   samples.Accumulate(1, 100);
   it = samples.Iterator();
   EXPECT_FALSE(it->Done());
 }
 #endif
 // (!defined(NDEBUG) || defined(DCHECK_ALWAYS_ON)) && GTEST_HAS_DEATH_TEST
 
-}  // namespace
 }  // namespace base