[NTP Snippets] Refactor background scheduling for remote suggestions

components/ntp_snippets/remote/scheduling_remote_suggestions_provider_unittest.cc

Index: components/ntp_snippets/remote/scheduling_remote_suggestions_provider_unittest.cc
diff --git a/components/ntp_snippets/remote/scheduling_remote_suggestions_provider_unittest.cc b/components/ntp_snippets/remote/scheduling_remote_suggestions_provider_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..3d3e19380312eb0ce138110db75397a71bdcdf6d
--- /dev/null
+++ b/components/ntp_snippets/remote/scheduling_remote_suggestions_provider_unittest.cc
@@ -0,0 +1,268 @@
+// Copyright 2016 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 "components/ntp_snippets/remote/scheduling_remote_suggestions_provider.h"
+
+#include <memory>
+#include <set>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "base/command_line.h"
+#include "base/macros.h"
+#include "base/memory/ptr_util.h"
+#include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
+#include "base/threading/thread_task_runner_handle.h"
+#include "base/time/time.h"
+#include "components/ntp_snippets/features.h"
+#include "components/ntp_snippets/ntp_snippets_constants.h"
+#include "components/ntp_snippets/pref_names.h"
+#include "components/ntp_snippets/remote/persistent_scheduler.h"
+#include "components/ntp_snippets/remote/remote_suggestions_provider.h"
+#include "components/ntp_snippets/remote/test_utils.h"
+#include "components/ntp_snippets/status.h"
+#include "components/ntp_snippets/user_classifier.h"
+#include "components/prefs/testing_pref_service.h"
+#include "components/variations/variations_params_manager.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using testing::ElementsAre;
+using testing::Eq;
+using testing::InSequence;
+using testing::Invoke;
+using testing::IsEmpty;
+using testing::Mock;
+using testing::MockFunction;
+using testing::Not;
+using testing::SaveArg;
+using testing::SizeIs;
+using testing::StartsWith;
+using testing::StrictMock;
+using testing::WithArgs;
+using testing::_;
+
+namespace ntp_snippets {
+
+namespace {
+
+const char* kDifferentInterval = "2";
+
+class MockPersistentScheduler : public PersistentScheduler {
+ public:
+  MOCK_METHOD2(Schedule,
+               bool(base::TimeDelta period_wifi,
+                    base::TimeDelta period_fallback));
+  MOCK_METHOD0(Unschedule, bool());
+};
+
+class MockRemoteSuggestionsProvider : public RemoteSuggestionsProvider {
+ public:
+  MOCK_METHOD1(SetProviderStatusCallback,
+               void(const ProviderStatusCallback& callback));
+  MOCK_METHOD1(RefetchInTheBackground,
+               void(const FetchStatusCallback& callback));
+};
+
+}  // namespace
+
+class SchedulingSchedulingRemoteSuggestionsProviderTest
+    : public ::testing::Test {
+ public:
+  SchedulingSchedulingRemoteSuggestionsProviderTest()
+      : user_classifier_(/*pref_service=*/nullptr) {
+    SchedulingRemoteSuggestionsProvider::RegisterProfilePrefs(
+        utils_.pref_service()->registry());
+  }
+
+  std::unique_ptr<SchedulingRemoteSuggestionsProvider>
+  MakeSchedulingProvider() {
+    auto provider =
+        base::MakeUnique<StrictMock<MockRemoteSuggestionsProvider>>();
+    provider_ = provider.get();
+
+    // Store the callback to be able to notify the scheduling provider later.
+    EXPECT_CALL(*provider_, SetProviderStatusCallback(_))
+        .SaveArg<0>(&provider_status_callback_);
+    auto scheduling_provider =
+        base::MakeUnique<SchedulingRemoteSuggestionsProvider>(
+            /*observer=*/nullptr, /*category_factory=*/nullptr,
+            std::move(provider), persistent_scheduler_, &user_classifier_,
+            utils_.pref_service());
+    return scheduler;
+  }
+
+  void ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus new_status) {
+    provider_status_callback_.Run(new_status);
+  }
+
+ protected:
+  StrictMock<MockPersistentScheduler> persistent_scheduler_;
+  StrictMock<MockRemoteSuggestionsProvider>* provider_;
+
+ private:
+  test::RemoteSuggestionsTestUtils utils_;
+  UserClassifier user_classifier_;
+  RemoteSuggestionsProvider::ProviderStatusCallback provider_status_callback_;
+
+  DISALLOW_COPY_AND_ASSIGN(SchedulingSchedulingRemoteSuggestionsProviderTest);
+};
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest,
+       ShouldFetchOnPersistentSchedulerWakeUp) {
+  auto provider = MakeSchedulingProvider();
+
+  EXPECT_CALL(provider_, RefetchInTheBackground(_));
+  provider->OnPersistentSchedulerWakeUp();
+}
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest,
+       ShouldRescheduleOnRescheduleFetching) {
+  auto provider = MakeSchedulingProvider();
+
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _));
+  provider->RescheduleFetching();
+}
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest, ShouldScheduleOnActivation) {
+  auto provider = MakeSchedulingProvider();
+
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _));
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+}
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest,
+       ShouldUnscheduleOnInactivation) {
+  auto provider = MakeSchedulingProvider();
+
+  EXPECT_CALL(persistent_scheduler_, Unschedule());
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::INACTIVE);
+}
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest,
+       ShouldUnscheduleOnLaterInactivation) {
+  auto provider = MakeSchedulingProvider();
+
+  {
+    InSequence s;
+    EXPECT_CALL(persistent_scheduler_, Schedule(_, _));
+    EXPECT_CALL(persistent_scheduler_, Unschedule());
+  }
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::INACTIVE);
+}
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest,
+       ShouldScheduleOnLaterActivation) {
+  auto provider = MakeSchedulingProvider();
+
+  {
+    InSequence s;
+    EXPECT_CALL(persistent_scheduler_, Unschedule(_, _));
+    EXPECT_CALL(persistent_scheduler_, Schedule());
+  }
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::INACTIVE);
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+}
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest,
+       ShouldRescheduleAfterSuccessfulFetch) {
+  auto provider = MakeSchedulingProvider();
+  // First reschedule on becoming active.
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _)).Times(2);
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+
+  // Trigger a fetch, save the callback and notify that the fetch has succeeded.
+  FetchStatusCallback callback;
+  EXPECT_CALL(provider_, RefetchInTheBackground(_)).SaveArg<0>(&callback);
+  provider->OnPersistentSchedulerWakeUp();
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _));
+  // Second reschedule after a successful fetch.
+  callback.Run(Status::Success());
+}
+
+TEST_F(SchedulingRemoteSuggestionsProviderTest,
+       ShouldNotRescheduleAfterFailedFetch) {
+  auto provider = MakeSchedulingProvider();
+  // Only reschedule on becoming active.
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _));
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+
+  // Trigger a fetch, save the callback and notify that the fetch has failed.
+  FetchStatusCallback callback;
+  EXPECT_CALL(provider_, RefetchInTheBackground(_)).SaveArg<0>(&callback);
+  provider->OnPersistentSchedulerWakeUp();
+  callback.Run(Status(StatusCode::PERMANENT_ERROR, ""));
+  // No furter reschedule after a failure.
+}
+
+TEST_F(RemoteSuggestionsSchedulerTest, ShouldScheduleOnlyOnce) {
+  auto provider = MakeSchedulingProvider();
+
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _));
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+  // No further call to Schedule on a second status callback.
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+}
+
+TEST_F(RemoteSuggestionsSchedulerTest, ShouldUnscheduleOnlyOnce) {
+  auto provider = MakeSchedulingProvider();
+
+  EXPECT_CALL(persistent_scheduler_, Unschedule());
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::INACTIVE);
+  // No further call to Unschedule on second status callback.
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::INACTIVE);
+}
+
+TEST_F(RemoteSuggestionsSchedulerTest, ReschedulesWhenWifiParamChanges) {
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _)).Times(2);
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+
+  // UserClassifier defaults to UserClass::ACTIVE_NTP_USER if PrefService is
+  // null. Change the wifi interval for this class.
+  variations::testing::VariationParamsManager params_manager(
+      ntp_snippets::kStudyName,
+      {{"fetching_interval_hours-wifi-active_ntp_user", kDifferentInterval}},
+      {kArticleSuggestionsFeature.name});
+
+  // Schedule() should get called for the second time after params have changed.
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+}
+
+TEST_F(RemoteSuggestionsSchedulerTest, ReschedulesWhenFallbackParamChanges) {
+  EXPECT_CALL(persistent_scheduler_, Schedule(_, _)).Times(2);
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+
+  // UserClassifier defaults to UserClass::ACTIVE_NTP_USER if PrefService is
+  // null. Change the wifi interval for this class.
+  variations::testing::VariationParamsManager params_manager(
+      ntp_snippets::kStudyName,
+      {{"fetching_interval_hours-fallback-active_ntp_user",
+        kDifferentInterval}},
+      {kArticleSuggestionsFeature.name});
+
+  // Schedule() should get called for the second time after params have changed.
+  ChangeStatusOfUnderlyingProvider(
+      RemoteSuggestionsProvider::ProviderStatus::ACTIVE);
+}
+
+}  // namespace ntp_snippets