Add DelayNavigationThrottle

chrome/browser/page_load_metrics/experiments/delay_navigation_throttle_unittest.cc

Index: chrome/browser/page_load_metrics/experiments/delay_navigation_throttle_unittest.cc
diff --git a/chrome/browser/page_load_metrics/experiments/delay_navigation_throttle_unittest.cc b/chrome/browser/page_load_metrics/experiments/delay_navigation_throttle_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..64ce8a45819e2ba87937fd842b1862577f0166ac
--- /dev/null
+++ b/chrome/browser/page_load_metrics/experiments/delay_navigation_throttle_unittest.cc
@@ -0,0 +1,213 @@
+// 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/experiments/delay_navigation_throttle.h"
+
+#include <map>
+#include <memory>
+#include <string>
+#include <tuple>
+#include <utility>
+
+#include "base/macros.h"
+#include "base/memory/ptr_util.h"
+#include "base/memory/ref_counted.h"
+#include "base/run_loop.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/test/scoped_feature_list.h"
+#include "base/test/test_mock_time_task_runner.h"
+#include "base/time/time.h"
+#include "chrome/test/base/chrome_render_view_host_test_harness.h"
+#include "components/variations/variations_associated_data.h"
+#include "content/public/browser/navigation_handle.h"
+#include "content/public/browser/navigation_throttle.h"
+#include "net/http/http_util.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "url/gurl.h"
+
+class DelayNavigationThrottleTest : public ChromeRenderViewHostTestHarness {};
+
+TEST_F(DelayNavigationThrottleTest, BasicDelay) {
+  const char kBasicResponseHeaders[] = "HTTP/1.1 200 OK";
+  base::TimeDelta navigation_delay = base::TimeDelta::FromSeconds(1);
+  GURL url("http://www.example.com/");
+
+  scoped_refptr<base::TestMockTimeTaskRunner> mock_time_task_runner(
+      new base::TestMockTimeTaskRunner());
+  std::unique_ptr<content::NavigationHandle> test_handle =
+      content::NavigationHandle::CreateNavigationHandleForTesting(url,
+                                                                  main_rfh());
+  test_handle->RegisterThrottleForTesting(
+      base::MakeUnique<DelayNavigationThrottle>(
+          test_handle.get(), mock_time_task_runner, navigation_delay));
+
+  EXPECT_FALSE(mock_time_task_runner->HasPendingTask());
+  EXPECT_EQ(content::NavigationThrottle::DEFER,
+            test_handle->CallWillStartRequestForTesting(
+                false /* is_post */, content::Referrer(),
+                false /* has_user_gesture */, ui::PAGE_TRANSITION_LINK,
+                false /* is_external_protocol */));
+
+  // There may be other throttles that DEFER and post async tasks to the UI
+  // thread. Allow them to run to completion, so our throttle is guaranteed to
+  // have a chance to run.
+  base::RunLoop().RunUntilIdle();
+
+  EXPECT_TRUE(mock_time_task_runner->HasPendingTask());
+  EXPECT_FALSE(test_handle->HasCommitted());
+
+  mock_time_task_runner->FastForwardBy(navigation_delay);
+  EXPECT_FALSE(mock_time_task_runner->HasPendingTask());
+
+  // Run any remaining async tasks, to make sure all other deferred throttles
+  // can complete.
+  base::RunLoop().RunUntilIdle();
+
+  // Verify that the WillSendRequest portion of the navigation has completed,
+  // and NavigationHandle::WillProcessResponse and the commit portion of the
+  // navigation lifetime can now be invoked.
+  EXPECT_EQ(content::NavigationThrottle::PROCEED,
+            test_handle->CallWillProcessResponseForTesting(
+                main_rfh(),
+                net::HttpUtil::AssembleRawHeaders(
+                    kBasicResponseHeaders, strlen(kBasicResponseHeaders))));
+  test_handle->CallDidCommitNavigationForTesting(url);
+  EXPECT_TRUE(test_handle->HasCommitted());
+}
+
+enum ExpectInstantiationResult {
+  EXPECT_INSTANTIATION,
+  EXPECT_NO_INSTANTIATION
+};
+
+class DelayNavigationThrottleInstantiationTest
+    : public ChromeRenderViewHostTestHarness,
+      public testing::WithParamInterface<
+          std::tuple<ExpectInstantiationResult,
+                     base::FeatureList::OverrideState,
+                     base::TimeDelta,
+                     bool,
+                     double,
+                     GURL>> {
+ public:
+  DelayNavigationThrottleInstantiationTest()
+      : field_trial_list_(nullptr /* entropy_provider */) {}
+
+  void SetUp() override {
+    ChromeRenderViewHostTestHarness::SetUp();
+
+    std::tie(expected_instantiation_result_, feature_state_, param_delay_,
+             param_randomize_delay_, param_probability_, url_) = GetParam();
+
+    std::map<std::string, std::string> variation_params(
+        {{DelayNavigationThrottle::kParamDelayNavigationDurationMillis,
+          base::IntToString(param_delay_.InMilliseconds())},
+         {DelayNavigationThrottle::kParamDelayNavigationRandomize,
+          param_randomize_delay_ ? "true" : "false"},
+         {DelayNavigationThrottle::kParamDelayNavigationProbability,
+          base::DoubleToString(param_probability_)}});
+    InitializeScopedFeatureList(feature_state_, variation_params);
+  }
+
+  void TearDown() override {
+    ChromeRenderViewHostTestHarness::TearDown();
+    variations::testing::ClearAllVariationParams();
+  }
+
+  void InitializeScopedFeatureList(
+      base::FeatureList::OverrideState feature_state,
+      const std::map<std::string, std::string>& variation_params) {
+    static const char kTestFieldTrialName[] = "TestTrial";
+    static const char kTestExperimentGroupName[] = "TestGroup";
+
+    EXPECT_TRUE(variations::AssociateVariationParams(
+        kTestFieldTrialName, kTestExperimentGroupName, variation_params));
+
+    base::FieldTrial* field_trial = base::FieldTrialList::CreateFieldTrial(
+        kTestFieldTrialName, kTestExperimentGroupName);
+
+    std::unique_ptr<base::FeatureList> feature_list(new base::FeatureList);
+    feature_list->RegisterFieldTrialOverride(kDelayNavigationFeature.name,
+                                             feature_state, field_trial);
+
+    // Since we are adding a scoped feature list after browser start, copy over
+    // the existing feature list to prevent inconsistency.
+    base::FeatureList* existing_feature_list = base::FeatureList::GetInstance();
+    if (existing_feature_list) {
+      std::string enabled_features;
+      std::string disabled_features;
+      base::FeatureList::GetInstance()->GetFeatureOverrides(&enabled_features,
+                                                            &disabled_features);
+      feature_list->InitializeFromCommandLine(enabled_features,
+                                              disabled_features);
+    }
+
+    scoped_feature_list_.InitWithFeatureList(std::move(feature_list));
+  }
+
+  base::FieldTrialList field_trial_list_;
+  base::test::ScopedFeatureList scoped_feature_list_;
+
+  // Fields filled in via GetParam():
+  base::FeatureList::OverrideState feature_state_;
+  base::TimeDelta param_delay_;
+  bool param_randomize_delay_ = false;
+  double param_probability_ = 0;
+  GURL url_;
+  ExpectInstantiationResult expected_instantiation_result_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DelayNavigationThrottleInstantiationTest);
+};
+
+TEST_P(DelayNavigationThrottleInstantiationTest, Instantiate) {
+  std::unique_ptr<content::NavigationHandle> test_handle =
+      content::NavigationHandle::CreateNavigationHandleForTesting(url_,
+                                                                  main_rfh());
+  std::unique_ptr<DelayNavigationThrottle> throttle =
+      DelayNavigationThrottle::MaybeCreateThrottleFor(test_handle.get());
+  const bool expect_instantiation =
+      expected_instantiation_result_ == EXPECT_INSTANTIATION;
+  EXPECT_EQ(expect_instantiation, throttle != nullptr);
+  if (throttle) {
+    base::TimeDelta delay = throttle->navigation_delay();
+    EXPECT_FALSE(delay.is_zero());
+    EXPECT_GE(param_delay_, delay);
+  }
+}
+
+INSTANTIATE_TEST_CASE_P(
+    InstantiateThrottle,
+    DelayNavigationThrottleInstantiationTest,
+    ::testing::Values(
+        std::make_tuple(EXPECT_NO_INSTANTIATION,
+                        base::FeatureList::OVERRIDE_DISABLE_FEATURE,
+                        base::TimeDelta::FromMilliseconds(10),
+                        false /* randomize delay */,
+                        1.0 /* delay probability */,
+                        GURL("http://www.example.com/")),
+        std::make_tuple(EXPECT_NO_INSTANTIATION,
+                        base::FeatureList::OVERRIDE_ENABLE_FEATURE,
+                        base::TimeDelta::FromMilliseconds(10),
+                        false /* randomize delay */,
+                        1.0 /* delay probability */,
+                        GURL("chrome://version")),
+        std::make_tuple(EXPECT_NO_INSTANTIATION,
+                        base::FeatureList::OVERRIDE_ENABLE_FEATURE,
+                        base::TimeDelta::FromMilliseconds(10),
+                        false /* randomize delay */,
+                        0.0 /* delay probability */,
+                        GURL("http://www.example.com/")),
+        std::make_tuple(EXPECT_INSTANTIATION,
+                        base::FeatureList::OVERRIDE_ENABLE_FEATURE,
+                        base::TimeDelta::FromMilliseconds(10),
+                        false /* randomize delay */,
+                        1.0 /* delay probability */,
+                        GURL("http://www.example.com/")),
+        std::make_tuple(EXPECT_INSTANTIATION,
+                        base::FeatureList::OVERRIDE_ENABLE_FEATURE,
+                        base::TimeDelta::FromMilliseconds(10),
+                        true /* randomize delay */,
+                        1.0 /* delay probability */,
+                        GURL("http://www.example.com/"))));