src/chrome/browser/chromeos/external_metrics_unittest.cc

   1 // Copyright (c) 2012 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/file_util.h"
   6 #include "base/files/scoped_temp_dir.h"
   7 #include "base/memory/scoped_ptr.h"
   8 #include "base/metrics/statistics_recorder.h"
   9 #include "chrome/browser/chromeos/external_metrics.h"
  10 #include "chrome/test/base/uma_histogram_helper.h"
  11 #include "components/metrics/serialization/metric_sample.h"
  12 #include "components/metrics/serialization/serialization_utils.h"
  13 #include "content/public/test/test_browser_thread_bundle.h"
  14
  15 namespace chromeos {  // Need this because of the FRIEND_TEST
  16
  17 class ExternalMetricsTest : public testing::Test {
  18  public:
  19   virtual void SetUp() OVERRIDE {
  20     ASSERT_TRUE(dir_.CreateUniqueTempDir());
  21     external_metrics_ = ExternalMetrics::CreateForTesting(
  22         dir_.path().Append("testfile").value());
  23
  24     base::StatisticsRecorder::Initialize();
  25   }
  26
  27   base::ScopedTempDir dir_;
  28   scoped_refptr<ExternalMetrics> external_metrics_;
  29   content::TestBrowserThreadBundle thread_bundle_;
  30 };
  31
  32 TEST_F(ExternalMetricsTest, HandleMissingFile) {
  33   ASSERT_TRUE(base::DeleteFile(
  34       base::FilePath(external_metrics_->uma_events_file_), false));
  35
  36   EXPECT_EQ(0, external_metrics_->CollectEvents());
  37 }
  38
  39 TEST_F(ExternalMetricsTest, CanReceiveHistogram) {
  40   scoped_ptr<metrics::MetricSample> hist =
  41       metrics::MetricSample::HistogramSample("foo", 2, 1, 100, 10);
  42
  43   EXPECT_TRUE(metrics::SerializationUtils::WriteMetricToFile(
  44       *hist.get(), external_metrics_->uma_events_file_));
  45
  46   EXPECT_EQ(1, external_metrics_->CollectEvents());
  47
  48   UMAHistogramHelper helper;
  49   helper.Fetch();
  50   helper.ExpectTotalCount("foo", 1);
  51 }
  52
  53 TEST_F(ExternalMetricsTest, IncorrectHistogramsAreDiscarded) {
  54   // Malformed histogram (min > max).
  55   scoped_ptr<metrics::MetricSample> hist =
  56       metrics::MetricSample::HistogramSample("bar", 30, 200, 20, 10);
  57
  58   EXPECT_TRUE(metrics::SerializationUtils::WriteMetricToFile(
  59       *hist.get(), external_metrics_->uma_events_file_));
  60
  61   external_metrics_->CollectEvents();
  62
  63   UMAHistogramHelper helper;
  64   helper.Fetch();
  65   helper.ExpectTotalCount("bar", 0);
  66 }
  67
  68 }  // namespace chromeos