SampleSet -> HistogramSamples (will be reused by SparseHistogram)

chrome/test/nacl/nacl_browsertest_uma.cc

Index: chrome/test/nacl/nacl_browsertest_uma.cc
===================================================================
--- chrome/test/nacl/nacl_browsertest_uma.cc	(revision 155400)
+++ chrome/test/nacl/nacl_browsertest_uma.cc	(working copy)
@@ -3,7 +3,9 @@
 // found in the LICENSE file.
 
 #include "base/bind.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
+#include "base/metrics/histogram_samples.h"
 #include "base/metrics/statistics_recorder.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "chrome/test/nacl/nacl_browsertest_util.h"
@@ -23,7 +25,8 @@
 
   // We know the exact number of samples in a bucket, and that no other bucket
   // should have samples.
-  void ExpectUniqueSample(const std::string& name, size_t bucket_id,
+  void ExpectUniqueSample(const std::string& name,
+                          base::Histogram::Sample sample,
                           base::Histogram::Count expected_count);
 
   // We don't know the values of the samples, but we know how many there are.
@@ -32,13 +35,14 @@
  private:
   void FetchCallback();
 
-  void CheckBucketCount(const std::string& name, size_t bucket_id,
+  void CheckBucketCount(const std::string& name,
+                        base::Histogram::Sample sample,
                         base::Histogram::Count expected_count,
-                        base::Histogram::SampleSet& samples);
+                        const base::HistogramSamples& samples);
 
   void CheckTotalCount(const std::string& name,
                        base::Histogram::Count expected_count,
-                       base::Histogram::SampleSet& samples);
+                       const base::HistogramSamples& samples);
 };
 
 HistogramHelper::HistogramHelper() {
@@ -60,16 +64,15 @@
 
 void HistogramHelper::ExpectUniqueSample(
     const std::string& name,
-    size_t bucket_id,
+    base::Histogram::Sample sample,
     base::Histogram::Count expected_count) {
   base::Histogram* histogram = base::StatisticsRecorder::FindHistogram(name);
   ASSERT_NE(static_cast<base::Histogram*>(NULL), histogram) <<
       "Histogram \"" << name << "\" does not exist.";
 
-  base::Histogram::SampleSet samples;
-  histogram->SnapshotSample(&samples);
-  CheckBucketCount(name, bucket_id, expected_count, samples);
-  CheckTotalCount(name, expected_count, samples);
+  scoped_ptr<base::HistogramSamples> samples(histogram->SnapshotSamples());
+  CheckBucketCount(name, sample, expected_count, *samples);
+  CheckTotalCount(name, expected_count, *samples);
 }
 
 void HistogramHelper::ExpectTotalCount(const std::string& name,
@@ -78,9 +81,8 @@
   ASSERT_NE((base::Histogram*)NULL, histogram) << "Histogram \"" << name <<
       "\" does not exist.";
 
-  base::Histogram::SampleSet samples;
-  histogram->SnapshotSample(&samples);
-  CheckTotalCount(name, count, samples);
+  scoped_ptr<base::HistogramSamples> samples(histogram->SnapshotSamples());
+  CheckTotalCount(name, count, *samples);
 }
 
 void HistogramHelper::FetchCallback() {
@@ -88,20 +90,22 @@
 }
 
 void HistogramHelper::CheckBucketCount(const std::string& name,
-                                       size_t bucket_id,
+                                       base::Histogram::Sample sample,
                                        base::Histogram::Count expected_count,
-                                       base::Histogram::SampleSet& samples) {
-  EXPECT_EQ(expected_count, samples.counts(bucket_id)) << "Histogram \"" <<
-      name << "\" does not have the right number of samples (" <<
-      expected_count << ") in the expected bucket (" << bucket_id << ").";
+                                       const base::HistogramSamples& samples) {
+  EXPECT_EQ(expected_count, samples.GetCount(sample))
+      << "Histogram \"" << name
+      << "\" does not have the right number of samples (" << expected_count
+      << ") in the expected bucket (" << sample << ").";
 }
 
 void HistogramHelper::CheckTotalCount(const std::string& name,
                                       base::Histogram::Count expected_count,
-                                      base::Histogram::SampleSet& samples) {
-  EXPECT_EQ(expected_count, samples.TotalCount()) << "Histogram \"" << name <<
-      "\" does not have the right total number of samples (" <<
-      expected_count << ").";
+                                      const base::HistogramSamples& samples) {
+  EXPECT_EQ(expected_count, samples.TotalCount())
+      << "Histogram \"" << name
+      << "\" does not have the right total number of samples ("
+      << expected_count << ").";
 }
 
 NACL_BROWSER_TEST_F(NaClBrowserTest, SuccessfulLoadUMA, {
@@ -114,12 +118,12 @@
   histograms.Fetch();
 
   // Did the plugin report success?
-  histograms.ExpectUniqueSample("NaCl.LoadStatus.Plugin",
-                                plugin::ERROR_LOAD_SUCCESS, 1);
+  histograms.ExpectUniqueSample(
+      "NaCl.LoadStatus.Plugin", plugin::ERROR_LOAD_SUCCESS, 1);

[Ilya Sherman, 2012/09/12 03:20:58]

nit: No need to re-wrap this line; the previous wrapping is fine.

 
   // Did the sel_ldr report success?
-  histograms.ExpectUniqueSample("NaCl.LoadStatus.SelLdr",
-                                LOAD_OK, 1);
+  histograms.ExpectUniqueSample(
+      "NaCl.LoadStatus.SelLdr", LOAD_OK, 1);

[Ilya Sherman, 2012/09/12 03:20:58]

nit: No need to re-wrap this line; the previous wrapping is fine.

[kaiwang, 2012/09/20 22:54:59]

they are more readable, in previous wrapping, it's hard to notice the function
call has 3 parameters

 
   // Make sure we have other important histograms.
   histograms.ExpectTotalCount("NaCl.Perf.StartupTime.LoadModule", 1);