components/sync_preferences/testing_pref_service_syncable.h

// Copyright (c) 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.

#ifndef COMPONENTS_SYNC_PREFERENCES_TESTING_PREF_SERVICE_SYNCABLE_H_
#define COMPONENTS_SYNC_PREFERENCES_TESTING_PREF_SERVICE_SYNCABLE_H_

#include "base/macros.h"
#include "components/prefs/testing_pref_service.h"
#include "components/sync_preferences/pref_service_syncable.h"

namespace user_prefs {
class PrefRegistrySyncable;
}

namespace sync_preferences {

// Test version of PrefServiceSyncable.
// This class hierarchy has a flaw: TestingPrefServiceBase is inheriting from
// the first template parameter (PrefServiceSyncable in this case). This means,
// all of the supported parameter types must support the same constructor
// signatures -- which they don't. Hence, it's not possible to properly inject
//  a PrefModelAssociatorClient.
// TODO(tschumann) The whole purpose of TestingPrefServiceBase is questionable
// and I'd be in favor of removing it completely:
//  -- it hides the dependency injetion of the different stores
//  -- just to later offer ways to manipulate speficic stores.
//  -- if tests just dependency injects the individual stores directly, they
//     already have full control and won't need that indirection at all.
// See PrefServiceSyncableMergeTest as an example of a cleaner way.
class TestingPrefServiceSyncable
    : public TestingPrefServiceBase<PrefServiceSyncable,
                                    user_prefs::PrefRegistrySyncable> {
 public:
  TestingPrefServiceSyncable();
  TestingPrefServiceSyncable(TestingPrefStore* managed_prefs,
                             TestingPrefStore* extension_prefs,
                             TestingPrefStore* user_prefs,
                             TestingPrefStore* recommended_prefs,
                             user_prefs::PrefRegistrySyncable* pref_registry,
                             PrefNotifierImpl* pref_notifier);
  ~TestingPrefServiceSyncable() override;

  // This is provided as a convenience; on a production PrefService
  // you would do all registrations before constructing it, passing it
  // a PrefRegistry via its constructor (or via e.g. PrefServiceFactory).
  user_prefs::PrefRegistrySyncable* registry();

 private:
  DISALLOW_COPY_AND_ASSIGN(TestingPrefServiceSyncable);
};

}  // namespace sync_preferences

template <>
TestingPrefServiceBase<sync_preferences::PrefServiceSyncable,
                       user_prefs::PrefRegistrySyncable>::
    TestingPrefServiceBase(TestingPrefStore* managed_prefs,
                           TestingPrefStore* extension_prefs,
                           TestingPrefStore* user_prefs,
                           TestingPrefStore* recommended_prefs,
                           user_prefs::PrefRegistrySyncable* pref_registry,
                           PrefNotifierImpl* pref_notifier);

#endif  // COMPONENTS_SYNC_PREFERENCES_TESTING_PREF_SERVICE_SYNCABLE_H_