Implement Dump-on-DCHECK (via a new LogSeverity).

base/metrics/sample_vector_unittest.cc

 // Copyright (c) 2012 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/sample_vector.h"
 
 #include <limits.h>
 #include <stddef.h>
 
 #include <memory>
@@ skipping 98 matching lines @@
   samples1.Subtract(samples2);
   EXPECT_EQ(100, samples1.GetCountAtIndex(0));
   EXPECT_EQ(0, samples1.GetCountAtIndex(1));
   EXPECT_EQ(100, samples1.GetCountAtIndex(2));
   EXPECT_EQ(100, samples1.GetCountAtIndex(3));
   EXPECT_EQ(600, samples1.sum());
   EXPECT_EQ(300, samples1.TotalCount());
   EXPECT_EQ(samples1.redundant_count(), samples1.TotalCount());
 }
 
-#if (!defined(NDEBUG) || defined(DCHECK_ALWAYS_ON)) && GTEST_HAS_DEATH_TEST
 TEST(SampleVectorDeathTest, BucketIndexTest) {
   // 8 buckets with exponential layout:
   // [0, 1) [1, 2) [2, 4) [4, 8) [8, 16) [16, 32) [32, 64) [64, INT_MAX)
   BucketRanges ranges(9);
   Histogram::InitializeBucketRanges(1, 64, &ranges);
   SampleVector samples(1, &ranges);
 
   // Normal case
   samples.Accumulate(0, 1);
   samples.Accumulate(3, 2);
   samples.Accumulate(64, 3);
   EXPECT_EQ(1, samples.GetCount(0));
   EXPECT_EQ(2, samples.GetCount(2));
   EXPECT_EQ(3, samples.GetCount(65));
 
   // Extreme case.
-  EXPECT_DEATH(samples.Accumulate(INT_MIN, 100), "");
-  EXPECT_DEATH(samples.Accumulate(-1, 100), "");
-  EXPECT_DEATH(samples.Accumulate(INT_MAX, 100), "");
+  EXPECT_DCHECK_DEATH(samples.Accumulate(INT_MIN, 100));
+  EXPECT_DCHECK_DEATH(samples.Accumulate(-1, 100));
+  EXPECT_DCHECK_DEATH(samples.Accumulate(INT_MAX, 100));

[Wez, 2016/12/19 23:57:46]

Q: Having DCHECK death-tests run but trivially pass doesn't seem helpful.  Can
we instead update the test infrastructure to be aware of death-tests and
DCHECK-tests - e.g:

DEATH_FooTest -> Run only if death tests are supported.
DCHECK_DEATH_FooTest -> Run only if DCHECK causes death on failure.

We could alternatively implement that via macros:

#define DCHECK_DEATH_NAME(test) ...

but that does make test names annoyingly verbose.

 
   // Custom buckets: [1, 5) [5, 10)
   // Note, this is not a valid BucketRanges for Histogram because it does not
   // have overflow buckets.
   BucketRanges ranges2(3);
   ranges2.set_range(0, 1);
   ranges2.set_range(1, 5);
   ranges2.set_range(2, 10);
   SampleVector samples2(2, &ranges2);
 
   // Normal case.
   samples2.Accumulate(1, 1);
   samples2.Accumulate(4, 1);
   samples2.Accumulate(5, 2);
   samples2.Accumulate(9, 2);
   EXPECT_EQ(2, samples2.GetCount(1));
   EXPECT_EQ(4, samples2.GetCount(5));
 
   // Extreme case.
-  EXPECT_DEATH(samples2.Accumulate(0, 100), "");
-  EXPECT_DEATH(samples2.Accumulate(10, 100), "");
+  EXPECT_DCHECK_DEATH(samples2.Accumulate(0, 100));
+  EXPECT_DCHECK_DEATH(samples2.Accumulate(10, 100));
 }
 
 TEST(SampleVectorDeathTest, AddSubtractBucketNotMatchTest) {
   // Custom buckets 1: [1, 3) [3, 5)
   BucketRanges ranges1(3);
   ranges1.set_range(0, 1);
   ranges1.set_range(1, 3);
   ranges1.set_range(2, 5);
   SampleVector samples1(1, &ranges1);
 
   // Custom buckets 2: [0, 1) [1, 3) [3, 6) [6, 7)
   BucketRanges ranges2(5);
   ranges2.set_range(0, 0);
   ranges2.set_range(1, 1);
   ranges2.set_range(2, 3);
   ranges2.set_range(3, 6);
   ranges2.set_range(4, 7);
   SampleVector samples2(2, &ranges2);
 
   samples2.Accumulate(1, 100);
   samples1.Add(samples2);
   EXPECT_EQ(100, samples1.GetCountAtIndex(0));
 
   // Extra bucket in the beginning.
   samples2.Accumulate(0, 100);
-  EXPECT_DEATH(samples1.Add(samples2), "");
-  EXPECT_DEATH(samples1.Subtract(samples2), "");
+  EXPECT_DCHECK_DEATH(samples1.Add(samples2));
+  EXPECT_DCHECK_DEATH(samples1.Subtract(samples2));
 
   // Extra bucket in the end.
   samples2.Accumulate(0, -100);
   samples2.Accumulate(6, 100);
-  EXPECT_DEATH(samples1.Add(samples2), "");
-  EXPECT_DEATH(samples1.Subtract(samples2), "");
+  EXPECT_DCHECK_DEATH(samples1.Add(samples2));
+  EXPECT_DCHECK_DEATH(samples1.Subtract(samples2));
 
   // Bucket not match: [3, 5) VS [3, 6)
   samples2.Accumulate(6, -100);
   samples2.Accumulate(3, 100);
-  EXPECT_DEATH(samples1.Add(samples2), "");
-  EXPECT_DEATH(samples1.Subtract(samples2), "");
+  EXPECT_DCHECK_DEATH(samples1.Add(samples2));
+  EXPECT_DCHECK_DEATH(samples1.Subtract(samples2));
 }
 
-#endif
-// (!defined(NDEBUG) || defined(DCHECK_ALWAYS_ON)) && GTEST_HAS_DEATH_TEST
-
 TEST(SampleVectorIteratorTest, IterateTest) {
   BucketRanges ranges(5);
   ranges.set_range(0, 0);
   ranges.set_range(1, 1);
   ranges.set_range(2, 2);
   ranges.set_range(3, 3);
   ranges.set_range(4, 4);
 
   std::vector<HistogramBase::Count> counts(3);
   counts[0] = 1;
@@ skipping 67 matching lines @@
 
   EXPECT_DCHECK_DEATH(it->Next());
 
   samples.Accumulate(2, 100);
   it = samples.Iterator();
   EXPECT_FALSE(it->Done());
 }
 
 }  // namespace
 }  // namespace base