Revert of Move base/prefs to components/prefs

base/prefs/scoped_user_pref_update_unittest.cc

+// Copyright 2013 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 "base/prefs/mock_pref_change_callback.h"
+#include "base/prefs/pref_change_registrar.h"
+#include "base/prefs/pref_registry_simple.h"
+#include "base/prefs/scoped_user_pref_update.h"
+#include "base/prefs/testing_pref_service.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using testing::_;
+using testing::Mock;
+
+class ScopedUserPrefUpdateTest : public testing::Test {
+ public:
+  ScopedUserPrefUpdateTest() : observer_(&prefs_) {}
+  ~ScopedUserPrefUpdateTest() override {}
+
+ protected:
+  void SetUp() override {
+    prefs_.registry()->RegisterDictionaryPref(kPref);
+    registrar_.Init(&prefs_);
+    registrar_.Add(kPref, observer_.GetCallback());
+  }
+
+  static const char kPref[];
+  static const char kKey[];
+  static const char kValue[];
+
+  TestingPrefServiceSimple prefs_;
+  MockPrefChangeCallback observer_;
+  PrefChangeRegistrar registrar_;
+};
+
+const char ScopedUserPrefUpdateTest::kPref[] = "name";
+const char ScopedUserPrefUpdateTest::kKey[] = "key";
+const char ScopedUserPrefUpdateTest::kValue[] = "value";
+
+TEST_F(ScopedUserPrefUpdateTest, RegularUse) {
+  // Dictionary that will be expected to be set at the end.
+  base::DictionaryValue expected_dictionary;
+  expected_dictionary.SetString(kKey, kValue);
+
+  {
+    EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
+    DictionaryPrefUpdate update(&prefs_, kPref);
+    base::DictionaryValue* value = update.Get();
+    ASSERT_TRUE(value);
+    value->SetString(kKey, kValue);
+
+    // The dictionary was created for us but the creation should have happened
+    // silently without notifications.
+    Mock::VerifyAndClearExpectations(&observer_);
+
+    // Modifications happen online and are instantly visible, though.
+    const base::DictionaryValue* current_value = prefs_.GetDictionary(kPref);
+    ASSERT_TRUE(current_value);
+    EXPECT_TRUE(expected_dictionary.Equals(current_value));
+
+    // Now we are leaving the scope of the update so we should be notified.
+    observer_.Expect(kPref, &expected_dictionary);
+  }
+  Mock::VerifyAndClearExpectations(&observer_);
+
+  const base::DictionaryValue* current_value = prefs_.GetDictionary(kPref);
+  ASSERT_TRUE(current_value);
+  EXPECT_TRUE(expected_dictionary.Equals(current_value));
+}
+
+TEST_F(ScopedUserPrefUpdateTest, NeverTouchAnything) {
+  const base::DictionaryValue* old_value = prefs_.GetDictionary(kPref);
+  EXPECT_CALL(observer_, OnPreferenceChanged(_)).Times(0);
+  {
+    DictionaryPrefUpdate update(&prefs_, kPref);
+  }
+  const base::DictionaryValue* new_value = prefs_.GetDictionary(kPref);
+  EXPECT_EQ(old_value, new_value);
+  Mock::VerifyAndClearExpectations(&observer_);
+}