predictors: Collect page load metrics for ResourcePrefetchPredictor.

chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer_unittest.cc

Index: chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer_unittest.cc
diff --git a/chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer_unittest.cc b/chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer_unittest.cc
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index 0000000000000000000000000000000000000000..bac976786bed6ff7aac17943bca331da9ccc425d
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+++ b/chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer_unittest.cc
@@ -0,0 +1,85 @@
+// Copyright 2017 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 "chrome/browser/page_load_metrics/observers/resource_prefetch_predictor_page_load_metrics_observer.h"
+
+#include "base/memory/ptr_util.h"
+#include "chrome/browser/page_load_metrics/observers/page_load_metrics_observer_test_harness.h"
+#include "chrome/browser/predictors/resource_prefetch_common.h"
+#include "chrome/browser/predictors/resource_prefetch_predictor.h"
+#include "chrome/test/base/testing_profile.h"
+#include "content/public/test/test_browser_thread_bundle.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+using predictors::ResourcePrefetchPredictor;
+
+class MockResourcePrefetchPredictor : public ResourcePrefetchPredictor {
+ public:
+  MockResourcePrefetchPredictor(
+      const predictors::ResourcePrefetchPredictorConfig& config,
+      Profile* profile)
+      : ResourcePrefetchPredictor(config, profile) {}
+
+  MOCK_METHOD1(IsUrlPrefetchable, bool(const GURL& main_frame_url));
+
+  ~MockResourcePrefetchPredictor() override {}
+};
+
+class ResourcePrefetchPredictorPageLoadMetricsObserverTest
+    : public page_load_metrics::PageLoadMetricsObserverTestHarness {
+ protected:
+  void SetUp() override {
+    page_load_metrics::PageLoadMetricsObserverTestHarness::SetUp();
+    predictors::ResourcePrefetchPredictorConfig config;
+    config.mode = predictors::ResourcePrefetchPredictorConfig::LEARNING;
+    predictor_ =
+        base::MakeUnique<testing::StrictMock<MockResourcePrefetchPredictor>>(
+            config, profile());
+    timing_.navigation_start = base::Time::FromDoubleT(1);
+    timing_.first_paint = base::TimeDelta::FromSeconds(2);
+    timing_.first_contentful_paint = base::TimeDelta::FromSeconds(3);
+    timing_.first_meaningful_paint = base::TimeDelta::FromSeconds(4);
+    PopulateRequiredTimingFields(&timing_);
+  }
+
+  void RegisterObservers(page_load_metrics::PageLoadTracker* tracker) override {
+    tracker->AddObserver(
+        base::MakeUnique<ResourcePrefetchPredictorPageLoadMetricsObserver>(
+            predictor_.get()));
+  }
+
+  std::unique_ptr<testing::StrictMock<MockResourcePrefetchPredictor>>
+      predictor_;
+  page_load_metrics::PageLoadTiming timing_;
+};
+
+TEST_F(ResourcePrefetchPredictorPageLoadMetricsObserverTest,
+       PrefetchableIsRecorded) {
+  const GURL main_frame_url("https://www.google.com");
+  EXPECT_CALL(*predictor_.get(), IsUrlPrefetchable(main_frame_url))
+      .WillOnce(testing::Return(true));
+
+  NavigateAndCommit(main_frame_url);
+  SimulateTimingUpdate(timing_);
+
+  histogram_tester().ExpectTotalCount(
+      internal::kHistogramResourcePrefetchPredictorFirstContentfulPaint, 1);
+  histogram_tester().ExpectTotalCount(
+      internal::kHistogramResourcePrefetchPredictorFirstMeaningfulPaint, 1);
+}
+
+TEST_F(ResourcePrefetchPredictorPageLoadMetricsObserverTest,
+       NotPrefetchableIsNotRecorded) {
+  const GURL main_frame_url("https://www.google.com");
+  EXPECT_CALL(*predictor_.get(), IsUrlPrefetchable(main_frame_url))
+      .WillOnce(testing::Return(false));
+
+  NavigateAndCommit(main_frame_url);
+  SimulateTimingUpdate(timing_);
+
+  histogram_tester().ExpectTotalCount(
+      internal::kHistogramResourcePrefetchPredictorFirstContentfulPaint, 0);
+  histogram_tester().ExpectTotalCount(
+      internal::kHistogramResourcePrefetchPredictorFirstMeaningfulPaint, 0);
+}