base/prefs/default_pref_store_unittest.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/prefs/default_pref_store.h"
   6 #include "testing/gtest/include/gtest/gtest.h"
   7
   8 using base::StringValue;
   9 using base::Value;
  10
  11 namespace {
  12
  13 class MockPrefStoreObserver : public PrefStore::Observer {
  14  public:
  15   explicit MockPrefStoreObserver(DefaultPrefStore* pref_store);
  16   virtual ~MockPrefStoreObserver();
  17
  18   int change_count() {
  19     return change_count_;
  20   }
  21
  22   // PrefStore::Observer implementation:
  23   virtual void OnPrefValueChanged(const std::string& key) OVERRIDE;
  24   virtual void OnInitializationCompleted(bool succeeded) OVERRIDE {}
  25
  26  private:
  27   DefaultPrefStore* pref_store_;
  28
  29   int change_count_;
  30
  31   DISALLOW_COPY_AND_ASSIGN(MockPrefStoreObserver);
  32 };
  33
  34 MockPrefStoreObserver::MockPrefStoreObserver(DefaultPrefStore* pref_store)
  35     : pref_store_(pref_store), change_count_(0) {
  36   pref_store_->AddObserver(this);
  37 }
  38
  39 MockPrefStoreObserver::~MockPrefStoreObserver() {
  40   pref_store_->RemoveObserver(this);
  41 }
  42
  43 void MockPrefStoreObserver::OnPrefValueChanged(const std::string& key) {
  44   change_count_++;
  45 }
  46
  47 }  // namespace
  48
  49 TEST(DefaultPrefStoreTest, NotifyPrefValueChanged) {
  50   scoped_refptr<DefaultPrefStore> pref_store(new DefaultPrefStore);
  51   MockPrefStoreObserver observer(pref_store.get());
  52   std::string kPrefKey("pref_key");
  53
  54   // Setting a default value shouldn't send a change notification.
  55   pref_store->SetDefaultValue(kPrefKey,
  56                               scoped_ptr<Value>(new StringValue("foo")));
  57   EXPECT_EQ(0, observer.change_count());
  58
  59   // Replacing the default value should send a change notification...
  60   pref_store->ReplaceDefaultValue(kPrefKey,
  61                                   scoped_ptr<Value>(new StringValue("bar")));
  62   EXPECT_EQ(1, observer.change_count());
  63
  64   // But only if the value actually changed.
  65   pref_store->ReplaceDefaultValue(kPrefKey,
  66                                   scoped_ptr<Value>(new StringValue("bar")));
  67   EXPECT_EQ(1, observer.change_count());
  68 }
  69