base/prefs/pref_service_unittest.cc - external/github.com/flutter/engine - Git at Google

 // Copyright (c) 2012 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 <string>

 #include "base/prefs/json_pref_store.h"
 #include "base/prefs/mock_pref_change_callback.h"
 #include "base/prefs/pref_change_registrar.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service_factory.h"
 #include "base/prefs/pref_value_store.h"
 #include "base/prefs/testing_pref_service.h"
 #include "base/prefs/testing_pref_store.h"
 #include "base/values.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"

 using testing::_;
 using testing::Mock;

 const char kPrefName[] = "pref.name";

 TEST(PrefServiceTest, NoObserverFire) {
   TestingPrefServiceSimple prefs;

   const char pref_name[] = "homepage";
   prefs.registry()->RegisterStringPref(pref_name, std::string());

   const char new_pref_value[] = "http://www.google.com/";
   MockPrefChangeCallback obs(&prefs);
   PrefChangeRegistrar registrar;
   registrar.Init(&prefs);
   registrar.Add(pref_name, obs.GetCallback());

   // This should fire the checks in MockPrefChangeCallback::OnPreferenceChanged.
   const base::StringValue expected_value(new_pref_value);
   obs.Expect(pref_name, &expected_value);
   prefs.SetString(pref_name, new_pref_value);
   Mock::VerifyAndClearExpectations(&obs);

   // Setting the pref to the same value should not set the pref value a second
   // time.
   EXPECT_CALL(obs, OnPreferenceChanged(_)).Times(0);
   prefs.SetString(pref_name, new_pref_value);
   Mock::VerifyAndClearExpectations(&obs);

   // Clearing the pref should cause the pref to fire.
   const base::StringValue expected_default_value((std::string()));
   obs.Expect(pref_name, &expected_default_value);
   prefs.ClearPref(pref_name);
   Mock::VerifyAndClearExpectations(&obs);

   // Clearing the pref again should not cause the pref to fire.
   EXPECT_CALL(obs, OnPreferenceChanged(_)).Times(0);
   prefs.ClearPref(pref_name);
   Mock::VerifyAndClearExpectations(&obs);
 }

 TEST(PrefServiceTest, HasPrefPath) {
   TestingPrefServiceSimple prefs;

   const char path[] = "fake.path";

   // Shouldn't initially have a path.
   EXPECT_FALSE(prefs.HasPrefPath(path));

   // Register the path. This doesn't set a value, so the path still shouldn't
   // exist.
   prefs.registry()->RegisterStringPref(path, std::string());
   EXPECT_FALSE(prefs.HasPrefPath(path));

   // Set a value and make sure we have a path.
   prefs.SetString(path, "blah");
   EXPECT_TRUE(prefs.HasPrefPath(path));
 }

 TEST(PrefServiceTest, Observers) {
   const char pref_name[] = "homepage";

   TestingPrefServiceSimple prefs;
   prefs.SetUserPref(pref_name,
                     new base::StringValue("http://www.cnn.com"));
   prefs.registry()->RegisterStringPref(pref_name, std::string());

   const char new_pref_value[] = "http://www.google.com/";
   const base::StringValue expected_new_pref_value(new_pref_value);
   MockPrefChangeCallback obs(&prefs);
   PrefChangeRegistrar registrar;
   registrar.Init(&prefs);
   registrar.Add(pref_name, obs.GetCallback());

   PrefChangeRegistrar registrar_two;
   registrar_two.Init(&prefs);

   // This should fire the checks in MockPrefChangeCallback::OnPreferenceChanged.
   obs.Expect(pref_name, &expected_new_pref_value);
   prefs.SetString(pref_name, new_pref_value);
   Mock::VerifyAndClearExpectations(&obs);

   // Now try adding a second pref observer.
   const char new_pref_value2[] = "http://www.youtube.com/";
   const base::StringValue expected_new_pref_value2(new_pref_value2);
   MockPrefChangeCallback obs2(&prefs);
   obs.Expect(pref_name, &expected_new_pref_value2);
   obs2.Expect(pref_name, &expected_new_pref_value2);
   registrar_two.Add(pref_name, obs2.GetCallback());
   // This should fire the checks in obs and obs2.
   prefs.SetString(pref_name, new_pref_value2);
   Mock::VerifyAndClearExpectations(&obs);
   Mock::VerifyAndClearExpectations(&obs2);

   // Set a recommended value.
   const base::StringValue recommended_pref_value("http://www.gmail.com/");
   obs.Expect(pref_name, &expected_new_pref_value2);
   obs2.Expect(pref_name, &expected_new_pref_value2);
   // This should fire the checks in obs and obs2 but with an unchanged value
   // as the recommended value is being overridden by the user-set value.
   prefs.SetRecommendedPref(pref_name, recommended_pref_value.DeepCopy());
   Mock::VerifyAndClearExpectations(&obs);
   Mock::VerifyAndClearExpectations(&obs2);

   // Make sure obs2 still works after removing obs.
   registrar.Remove(pref_name);
   EXPECT_CALL(obs, OnPreferenceChanged(_)).Times(0);
   obs2.Expect(pref_name, &expected_new_pref_value);
   // This should only fire the observer in obs2.
   prefs.SetString(pref_name, new_pref_value);
   Mock::VerifyAndClearExpectations(&obs);
   Mock::VerifyAndClearExpectations(&obs2);
 }

 // Make sure that if a preference changes type, so the wrong type is stored in
 // the user pref file, it uses the correct fallback value instead.
 TEST(PrefServiceTest, GetValueChangedType) {
   const int kTestValue = 10;
   TestingPrefServiceSimple prefs;
   prefs.registry()->RegisterIntegerPref(kPrefName, kTestValue);

   // Check falling back to a recommended value.
   prefs.SetUserPref(kPrefName,
                     new base::StringValue("not an integer"));
   const PrefService::Preference* pref = prefs.FindPreference(kPrefName);
   ASSERT_TRUE(pref);
   const base::Value* value = pref->GetValue();
   ASSERT_TRUE(value);
   EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
   int actual_int_value = -1;
   EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
   EXPECT_EQ(kTestValue, actual_int_value);
 }

 TEST(PrefServiceTest, GetValueAndGetRecommendedValue) {
   const int kDefaultValue = 5;
   const int kUserValue = 10;
   const int kRecommendedValue = 15;
   TestingPrefServiceSimple prefs;
   prefs.registry()->RegisterIntegerPref(kPrefName, kDefaultValue);

   // Create pref with a default value only.
   const PrefService::Preference* pref = prefs.FindPreference(kPrefName);
   ASSERT_TRUE(pref);

   // Check that GetValue() returns the default value.
   const base::Value* value = pref->GetValue();
   ASSERT_TRUE(value);
   EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
   int actual_int_value = -1;
   EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
   EXPECT_EQ(kDefaultValue, actual_int_value);

   // Check that GetRecommendedValue() returns no value.
   value = pref->GetRecommendedValue();
   ASSERT_FALSE(value);

   // Set a user-set value.
   prefs.SetUserPref(kPrefName, new base::FundamentalValue(kUserValue));

   // Check that GetValue() returns the user-set value.
   value = pref->GetValue();
   ASSERT_TRUE(value);
   EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
   actual_int_value = -1;
   EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
   EXPECT_EQ(kUserValue, actual_int_value);

   // Check that GetRecommendedValue() returns no value.
   value = pref->GetRecommendedValue();
   ASSERT_FALSE(value);

   // Set a recommended value.
   prefs.SetRecommendedPref(kPrefName,
                            new base::FundamentalValue(kRecommendedValue));

   // Check that GetValue() returns the user-set value.
   value = pref->GetValue();
   ASSERT_TRUE(value);
   EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
   actual_int_value = -1;
   EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
   EXPECT_EQ(kUserValue, actual_int_value);

   // Check that GetRecommendedValue() returns the recommended value.
   value = pref->GetRecommendedValue();
   ASSERT_TRUE(value);
   EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
   actual_int_value = -1;
   EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
   EXPECT_EQ(kRecommendedValue, actual_int_value);

   // Remove the user-set value.
   prefs.RemoveUserPref(kPrefName);

   // Check that GetValue() returns the recommended value.
   value = pref->GetValue();
   ASSERT_TRUE(value);
   EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
   actual_int_value = -1;
   EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
   EXPECT_EQ(kRecommendedValue, actual_int_value);

   // Check that GetRecommendedValue() returns the recommended value.
   value = pref->GetRecommendedValue();
   ASSERT_TRUE(value);
   EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
   actual_int_value = -1;
   EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
   EXPECT_EQ(kRecommendedValue, actual_int_value);
 }

 // A PrefStore which just stores the last write flags that were used to write
 // values to it.
 class WriteFlagChecker : public TestingPrefStore {
  public:
   WriteFlagChecker() {}

   void ReportValueChanged(const std::string& key, uint32 flags) override {
     SetLastWriteFlags(flags);
   }

   void SetValue(const std::string& key,
                 scoped_ptr<base::Value> value,
                 uint32 flags) override {
     SetLastWriteFlags(flags);
   }

   void SetValueSilently(const std::string& key,
                         scoped_ptr<base::Value> value,
                         uint32 flags) override {
     SetLastWriteFlags(flags);
   }

   void RemoveValue(const std::string& key, uint32 flags) override {
     SetLastWriteFlags(flags);
   }

   uint32 GetLastFlagsAndClear() {
     CHECK(last_write_flags_set_);
     uint32 result = last_write_flags_;
     last_write_flags_set_ = false;
     last_write_flags_ = WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS;
     return result;
   }

   bool last_write_flags_set() { return last_write_flags_set_; }

  private:
   ~WriteFlagChecker() override {}

   void SetLastWriteFlags(uint32 flags) {
     CHECK(!last_write_flags_set_);
     last_write_flags_set_ = true;
     last_write_flags_ = flags;
   }

   bool last_write_flags_set_ = false;
   uint32 last_write_flags_ = WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS;
 };

 TEST(PrefServiceTest, WriteablePrefStoreFlags) {
   scoped_refptr<WriteFlagChecker> flag_checker(new WriteFlagChecker);
   scoped_refptr<PrefRegistrySimple> registry(new PrefRegistrySimple);
   base::PrefServiceFactory factory;
   factory.set_user_prefs(flag_checker);
   scoped_ptr<PrefService> prefs(factory.Create(registry.get()));

   // The first 8 bits of write flags are reserved for subclasses. Create a
   // custom flag in this range
   uint32 kCustomRegistrationFlag = 1 << 2;

   // A map of the registration flags that will be tested and the write flags
   // they are expected to convert to.
   struct RegistrationToWriteFlags {
     const char* pref_name;
     uint32 registration_flags;
     uint32 write_flags;
   };
   const RegistrationToWriteFlags kRegistrationToWriteFlags[] = {
       {"none",
        PrefRegistry::NO_REGISTRATION_FLAGS,
        WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS},
       {"lossy",
        PrefRegistry::LOSSY_PREF,
        WriteablePrefStore::LOSSY_PREF_WRITE_FLAG},
       {"custom",
        kCustomRegistrationFlag,
        WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS},
       {"lossyandcustom",
        PrefRegistry::LOSSY_PREF | kCustomRegistrationFlag,
        WriteablePrefStore::LOSSY_PREF_WRITE_FLAG}};

   for (size_t i = 0; i < arraysize(kRegistrationToWriteFlags); ++i) {
     RegistrationToWriteFlags entry = kRegistrationToWriteFlags[i];
     registry->RegisterDictionaryPref(
         entry.pref_name, new base::DictionaryValue(), entry.registration_flags);

     SCOPED_TRACE("Currently testing pref with name: " +
                  std::string(entry.pref_name));

     prefs->GetMutableUserPref(entry.pref_name, base::Value::TYPE_DICTIONARY);
     EXPECT_TRUE(flag_checker->last_write_flags_set());
     EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());

     prefs->ReportUserPrefChanged(entry.pref_name);
     EXPECT_TRUE(flag_checker->last_write_flags_set());
     EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());

     prefs->ClearPref(entry.pref_name);
     EXPECT_TRUE(flag_checker->last_write_flags_set());
     EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());

     prefs->SetUserPrefValue(entry.pref_name, new base::DictionaryValue());
     EXPECT_TRUE(flag_checker->last_write_flags_set());
     EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());
   }
 }

 class PrefServiceSetValueTest : public testing::Test {
  protected:
   static const char kName[];
   static const char kValue[];

   PrefServiceSetValueTest() : observer_(&prefs_) {}

   TestingPrefServiceSimple prefs_;
   MockPrefChangeCallback observer_;
 };

 const char PrefServiceSetValueTest::kName[] = "name";
 const char PrefServiceSetValueTest::kValue[] = "value";

 TEST_F(PrefServiceSetValueTest, SetStringValue) {
   const char default_string[] = "default";
   const base::StringValue default_value(default_string);
   prefs_.registry()->RegisterStringPref(kName, default_string);

   PrefChangeRegistrar registrar;
   registrar.Init(&prefs_);
   registrar.Add(kName, observer_.GetCallback());

   // Changing the controlling store from default to user triggers notification.
   observer_.Expect(kName, &default_value);
   prefs_.Set(kName, default_value);
   Mock::VerifyAndClearExpectations(&observer_);

   EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
   prefs_.Set(kName, default_value);
   Mock::VerifyAndClearExpectations(&observer_);

   base::StringValue new_value(kValue);
   observer_.Expect(kName, &new_value);
   prefs_.Set(kName, new_value);
   Mock::VerifyAndClearExpectations(&observer_);
 }

 TEST_F(PrefServiceSetValueTest, SetDictionaryValue) {
   prefs_.registry()->RegisterDictionaryPref(kName);
   PrefChangeRegistrar registrar;
   registrar.Init(&prefs_);
   registrar.Add(kName, observer_.GetCallback());

   EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
   prefs_.RemoveUserPref(kName);
   Mock::VerifyAndClearExpectations(&observer_);

   base::DictionaryValue new_value;
   new_value.SetString(kName, kValue);
   observer_.Expect(kName, &new_value);
   prefs_.Set(kName, new_value);
   Mock::VerifyAndClearExpectations(&observer_);

   EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
   prefs_.Set(kName, new_value);
   Mock::VerifyAndClearExpectations(&observer_);

   base::DictionaryValue empty;
   observer_.Expect(kName, &empty);
   prefs_.Set(kName, empty);
   Mock::VerifyAndClearExpectations(&observer_);
 }

 TEST_F(PrefServiceSetValueTest, SetListValue) {
   prefs_.registry()->RegisterListPref(kName);
   PrefChangeRegistrar registrar;
   registrar.Init(&prefs_);
   registrar.Add(kName, observer_.GetCallback());

   EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
   prefs_.RemoveUserPref(kName);
   Mock::VerifyAndClearExpectations(&observer_);

   base::ListValue new_value;
   new_value.Append(new base::StringValue(kValue));
   observer_.Expect(kName, &new_value);
   prefs_.Set(kName, new_value);
   Mock::VerifyAndClearExpectations(&observer_);

   EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
   prefs_.Set(kName, new_value);
   Mock::VerifyAndClearExpectations(&observer_);

   base::ListValue empty;
   observer_.Expect(kName, &empty);
   prefs_.Set(kName, empty);
   Mock::VerifyAndClearExpectations(&observer_);
 }
	// Copyright (c) 2012 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 <string>

	#include "base/prefs/json_pref_store.h"
	#include "base/prefs/mock_pref_change_callback.h"
	#include "base/prefs/pref_change_registrar.h"
	#include "base/prefs/pref_registry_simple.h"
	#include "base/prefs/pref_service_factory.h"
	#include "base/prefs/pref_value_store.h"
	#include "base/prefs/testing_pref_service.h"
	#include "base/prefs/testing_pref_store.h"
	#include "base/values.h"
	#include "testing/gmock/include/gmock/gmock.h"
	#include "testing/gtest/include/gtest/gtest.h"

	using testing::_;
	using testing::Mock;

	const char kPrefName[] = "pref.name";

	TEST(PrefServiceTest, NoObserverFire) {
	TestingPrefServiceSimple prefs;

	const char pref_name[] = "homepage";
	prefs.registry()->RegisterStringPref(pref_name, std::string());

	const char new_pref_value[] = "http://www.google.com/";
	MockPrefChangeCallback obs(&prefs);
	PrefChangeRegistrar registrar;
	registrar.Init(&prefs);
	registrar.Add(pref_name, obs.GetCallback());

	// This should fire the checks in MockPrefChangeCallback::OnPreferenceChanged.
	const base::StringValue expected_value(new_pref_value);
	obs.Expect(pref_name, &expected_value);
	prefs.SetString(pref_name, new_pref_value);
	Mock::VerifyAndClearExpectations(&obs);

	// Setting the pref to the same value should not set the pref value a second
	// time.
	EXPECT_CALL(obs, OnPreferenceChanged(_)).Times(0);
	prefs.SetString(pref_name, new_pref_value);
	Mock::VerifyAndClearExpectations(&obs);

	// Clearing the pref should cause the pref to fire.
	const base::StringValue expected_default_value((std::string()));
	obs.Expect(pref_name, &expected_default_value);
	prefs.ClearPref(pref_name);
	Mock::VerifyAndClearExpectations(&obs);

	// Clearing the pref again should not cause the pref to fire.
	EXPECT_CALL(obs, OnPreferenceChanged(_)).Times(0);
	prefs.ClearPref(pref_name);
	Mock::VerifyAndClearExpectations(&obs);
	}

	TEST(PrefServiceTest, HasPrefPath) {
	TestingPrefServiceSimple prefs;

	const char path[] = "fake.path";

	// Shouldn't initially have a path.
	EXPECT_FALSE(prefs.HasPrefPath(path));

	// Register the path. This doesn't set a value, so the path still shouldn't
	// exist.
	prefs.registry()->RegisterStringPref(path, std::string());
	EXPECT_FALSE(prefs.HasPrefPath(path));

	// Set a value and make sure we have a path.
	prefs.SetString(path, "blah");
	EXPECT_TRUE(prefs.HasPrefPath(path));
	}

	TEST(PrefServiceTest, Observers) {
	const char pref_name[] = "homepage";

	TestingPrefServiceSimple prefs;
	prefs.SetUserPref(pref_name,
	new base::StringValue("http://www.cnn.com"));
	prefs.registry()->RegisterStringPref(pref_name, std::string());

	const char new_pref_value[] = "http://www.google.com/";
	const base::StringValue expected_new_pref_value(new_pref_value);
	MockPrefChangeCallback obs(&prefs);
	PrefChangeRegistrar registrar;
	registrar.Init(&prefs);
	registrar.Add(pref_name, obs.GetCallback());

	PrefChangeRegistrar registrar_two;
	registrar_two.Init(&prefs);

	// This should fire the checks in MockPrefChangeCallback::OnPreferenceChanged.
	obs.Expect(pref_name, &expected_new_pref_value);
	prefs.SetString(pref_name, new_pref_value);
	Mock::VerifyAndClearExpectations(&obs);

	// Now try adding a second pref observer.
	const char new_pref_value2[] = "http://www.youtube.com/";
	const base::StringValue expected_new_pref_value2(new_pref_value2);
	MockPrefChangeCallback obs2(&prefs);
	obs.Expect(pref_name, &expected_new_pref_value2);
	obs2.Expect(pref_name, &expected_new_pref_value2);
	registrar_two.Add(pref_name, obs2.GetCallback());
	// This should fire the checks in obs and obs2.
	prefs.SetString(pref_name, new_pref_value2);
	Mock::VerifyAndClearExpectations(&obs);
	Mock::VerifyAndClearExpectations(&obs2);

	// Set a recommended value.
	const base::StringValue recommended_pref_value("http://www.gmail.com/");
	obs.Expect(pref_name, &expected_new_pref_value2);
	obs2.Expect(pref_name, &expected_new_pref_value2);
	// This should fire the checks in obs and obs2 but with an unchanged value
	// as the recommended value is being overridden by the user-set value.
	prefs.SetRecommendedPref(pref_name, recommended_pref_value.DeepCopy());
	Mock::VerifyAndClearExpectations(&obs);
	Mock::VerifyAndClearExpectations(&obs2);

	// Make sure obs2 still works after removing obs.
	registrar.Remove(pref_name);
	EXPECT_CALL(obs, OnPreferenceChanged(_)).Times(0);
	obs2.Expect(pref_name, &expected_new_pref_value);
	// This should only fire the observer in obs2.
	prefs.SetString(pref_name, new_pref_value);
	Mock::VerifyAndClearExpectations(&obs);
	Mock::VerifyAndClearExpectations(&obs2);
	}

	// Make sure that if a preference changes type, so the wrong type is stored in
	// the user pref file, it uses the correct fallback value instead.
	TEST(PrefServiceTest, GetValueChangedType) {
	const int kTestValue = 10;
	TestingPrefServiceSimple prefs;
	prefs.registry()->RegisterIntegerPref(kPrefName, kTestValue);

	// Check falling back to a recommended value.
	prefs.SetUserPref(kPrefName,
	new base::StringValue("not an integer"));
	const PrefService::Preference* pref = prefs.FindPreference(kPrefName);
	ASSERT_TRUE(pref);
	const base::Value* value = pref->GetValue();
	ASSERT_TRUE(value);
	EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
	int actual_int_value = -1;
	EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
	EXPECT_EQ(kTestValue, actual_int_value);
	}

	TEST(PrefServiceTest, GetValueAndGetRecommendedValue) {
	const int kDefaultValue = 5;
	const int kUserValue = 10;
	const int kRecommendedValue = 15;
	TestingPrefServiceSimple prefs;
	prefs.registry()->RegisterIntegerPref(kPrefName, kDefaultValue);

	// Create pref with a default value only.
	const PrefService::Preference* pref = prefs.FindPreference(kPrefName);
	ASSERT_TRUE(pref);

	// Check that GetValue() returns the default value.
	const base::Value* value = pref->GetValue();
	ASSERT_TRUE(value);
	EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
	int actual_int_value = -1;
	EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
	EXPECT_EQ(kDefaultValue, actual_int_value);

	// Check that GetRecommendedValue() returns no value.
	value = pref->GetRecommendedValue();
	ASSERT_FALSE(value);

	// Set a user-set value.
	prefs.SetUserPref(kPrefName, new base::FundamentalValue(kUserValue));

	// Check that GetValue() returns the user-set value.
	value = pref->GetValue();
	ASSERT_TRUE(value);
	EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
	actual_int_value = -1;
	EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
	EXPECT_EQ(kUserValue, actual_int_value);

	// Check that GetRecommendedValue() returns no value.
	value = pref->GetRecommendedValue();
	ASSERT_FALSE(value);

	// Set a recommended value.
	prefs.SetRecommendedPref(kPrefName,
	new base::FundamentalValue(kRecommendedValue));

	// Check that GetValue() returns the user-set value.
	value = pref->GetValue();
	ASSERT_TRUE(value);
	EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
	actual_int_value = -1;
	EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
	EXPECT_EQ(kUserValue, actual_int_value);

	// Check that GetRecommendedValue() returns the recommended value.
	value = pref->GetRecommendedValue();
	ASSERT_TRUE(value);
	EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
	actual_int_value = -1;
	EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
	EXPECT_EQ(kRecommendedValue, actual_int_value);

	// Remove the user-set value.
	prefs.RemoveUserPref(kPrefName);

	// Check that GetValue() returns the recommended value.
	value = pref->GetValue();
	ASSERT_TRUE(value);
	EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
	actual_int_value = -1;
	EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
	EXPECT_EQ(kRecommendedValue, actual_int_value);

	// Check that GetRecommendedValue() returns the recommended value.
	value = pref->GetRecommendedValue();
	ASSERT_TRUE(value);
	EXPECT_EQ(base::Value::TYPE_INTEGER, value->GetType());
	actual_int_value = -1;
	EXPECT_TRUE(value->GetAsInteger(&actual_int_value));
	EXPECT_EQ(kRecommendedValue, actual_int_value);
	}

	// A PrefStore which just stores the last write flags that were used to write
	// values to it.
	class WriteFlagChecker : public TestingPrefStore {
	public:
	WriteFlagChecker() {}

	void ReportValueChanged(const std::string& key, uint32 flags) override {
	SetLastWriteFlags(flags);
	}

	void SetValue(const std::string& key,
	scoped_ptr<base::Value> value,
	uint32 flags) override {
	SetLastWriteFlags(flags);
	}

	void SetValueSilently(const std::string& key,
	scoped_ptr<base::Value> value,
	uint32 flags) override {
	SetLastWriteFlags(flags);
	}

	void RemoveValue(const std::string& key, uint32 flags) override {
	SetLastWriteFlags(flags);
	}

	uint32 GetLastFlagsAndClear() {
	CHECK(last_write_flags_set_);
	uint32 result = last_write_flags_;
	last_write_flags_set_ = false;
	last_write_flags_ = WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS;
	return result;
	}

	bool last_write_flags_set() { return last_write_flags_set_; }

	private:
	~WriteFlagChecker() override {}

	void SetLastWriteFlags(uint32 flags) {
	CHECK(!last_write_flags_set_);
	last_write_flags_set_ = true;
	last_write_flags_ = flags;
	}

	bool last_write_flags_set_ = false;
	uint32 last_write_flags_ = WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS;
	};

	TEST(PrefServiceTest, WriteablePrefStoreFlags) {
	scoped_refptr<WriteFlagChecker> flag_checker(new WriteFlagChecker);
	scoped_refptr<PrefRegistrySimple> registry(new PrefRegistrySimple);
	base::PrefServiceFactory factory;
	factory.set_user_prefs(flag_checker);
	scoped_ptr<PrefService> prefs(factory.Create(registry.get()));

	// The first 8 bits of write flags are reserved for subclasses. Create a
	// custom flag in this range
	uint32 kCustomRegistrationFlag = 1 << 2;

	// A map of the registration flags that will be tested and the write flags
	// they are expected to convert to.
	struct RegistrationToWriteFlags {
	const char* pref_name;
	uint32 registration_flags;
	uint32 write_flags;
	};
	const RegistrationToWriteFlags kRegistrationToWriteFlags[] = {
	{"none",
	PrefRegistry::NO_REGISTRATION_FLAGS,
	WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS},
	{"lossy",
	PrefRegistry::LOSSY_PREF,
	WriteablePrefStore::LOSSY_PREF_WRITE_FLAG},
	{"custom",
	kCustomRegistrationFlag,
	WriteablePrefStore::DEFAULT_PREF_WRITE_FLAGS},
	{"lossyandcustom",
	PrefRegistry::LOSSY_PREF \| kCustomRegistrationFlag,
	WriteablePrefStore::LOSSY_PREF_WRITE_FLAG}};

	for (size_t i = 0; i < arraysize(kRegistrationToWriteFlags); ++i) {
	RegistrationToWriteFlags entry = kRegistrationToWriteFlags[i];
	registry->RegisterDictionaryPref(
	entry.pref_name, new base::DictionaryValue(), entry.registration_flags);

	SCOPED_TRACE("Currently testing pref with name: " +
	std::string(entry.pref_name));

	prefs->GetMutableUserPref(entry.pref_name, base::Value::TYPE_DICTIONARY);
	EXPECT_TRUE(flag_checker->last_write_flags_set());
	EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());

	prefs->ReportUserPrefChanged(entry.pref_name);
	EXPECT_TRUE(flag_checker->last_write_flags_set());
	EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());

	prefs->ClearPref(entry.pref_name);
	EXPECT_TRUE(flag_checker->last_write_flags_set());
	EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());

	prefs->SetUserPrefValue(entry.pref_name, new base::DictionaryValue());
	EXPECT_TRUE(flag_checker->last_write_flags_set());
	EXPECT_EQ(entry.write_flags, flag_checker->GetLastFlagsAndClear());
	}
	}

	class PrefServiceSetValueTest : public testing::Test {
	protected:
	static const char kName[];
	static const char kValue[];

	PrefServiceSetValueTest() : observer_(&prefs_) {}

	TestingPrefServiceSimple prefs_;
	MockPrefChangeCallback observer_;
	};

	const char PrefServiceSetValueTest::kName[] = "name";
	const char PrefServiceSetValueTest::kValue[] = "value";

	TEST_F(PrefServiceSetValueTest, SetStringValue) {
	const char default_string[] = "default";
	const base::StringValue default_value(default_string);
	prefs_.registry()->RegisterStringPref(kName, default_string);

	PrefChangeRegistrar registrar;
	registrar.Init(&prefs_);
	registrar.Add(kName, observer_.GetCallback());

	// Changing the controlling store from default to user triggers notification.
	observer_.Expect(kName, &default_value);
	prefs_.Set(kName, default_value);
	Mock::VerifyAndClearExpectations(&observer_);

	EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
	prefs_.Set(kName, default_value);
	Mock::VerifyAndClearExpectations(&observer_);

	base::StringValue new_value(kValue);
	observer_.Expect(kName, &new_value);
	prefs_.Set(kName, new_value);
	Mock::VerifyAndClearExpectations(&observer_);
	}

	TEST_F(PrefServiceSetValueTest, SetDictionaryValue) {
	prefs_.registry()->RegisterDictionaryPref(kName);
	PrefChangeRegistrar registrar;
	registrar.Init(&prefs_);
	registrar.Add(kName, observer_.GetCallback());

	EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
	prefs_.RemoveUserPref(kName);
	Mock::VerifyAndClearExpectations(&observer_);

	base::DictionaryValue new_value;
	new_value.SetString(kName, kValue);
	observer_.Expect(kName, &new_value);
	prefs_.Set(kName, new_value);
	Mock::VerifyAndClearExpectations(&observer_);

	EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
	prefs_.Set(kName, new_value);
	Mock::VerifyAndClearExpectations(&observer_);

	base::DictionaryValue empty;
	observer_.Expect(kName, &empty);
	prefs_.Set(kName, empty);
	Mock::VerifyAndClearExpectations(&observer_);
	}

	TEST_F(PrefServiceSetValueTest, SetListValue) {
	prefs_.registry()->RegisterListPref(kName);
	PrefChangeRegistrar registrar;
	registrar.Init(&prefs_);
	registrar.Add(kName, observer_.GetCallback());

	EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
	prefs_.RemoveUserPref(kName);
	Mock::VerifyAndClearExpectations(&observer_);

	base::ListValue new_value;
	new_value.Append(new base::StringValue(kValue));
	observer_.Expect(kName, &new_value);
	prefs_.Set(kName, new_value);
	Mock::VerifyAndClearExpectations(&observer_);

	EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
	prefs_.Set(kName, new_value);
	Mock::VerifyAndClearExpectations(&observer_);

	base::ListValue empty;
	observer_.Expect(kName, &empty);
	prefs_.Set(kName, empty);
	Mock::VerifyAndClearExpectations(&observer_);
	}