Add sync manager classes for backup/rollback:

sync/internal_api/sync_rollback_manager_unittest.cc

+// Copyright 2014 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 "sync/internal_api/sync_rollback_manager.h"
+
+#include "sql/connection.h"
+#include "sync/internal_api/public/read_node.h"
+#include "sync/internal_api/public/read_transaction.h"
+#include "sync/internal_api/public/test/test_internal_components_factory.h"
+#include "sync/internal_api/public/write_node.h"
+#include "sync/internal_api/public/write_transaction.h"
+#include "sync/internal_api/sync_backup_manager.h"
+#include "sync/syncable/entry.h"
+#include "sync/test/engine/fake_model_worker.h"
+#include "sync/test/test_directory_backing_store.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+using ::testing::_;
+using ::testing::Invoke;
+using ::testing::WithArgs;
+
+namespace syncer {
+
+class SyncRollbackManagerTest

[Nicolas Zea, 2014/04/14 21:36:31]

put this all within an anon namespace?

[haitaol1, 2014/04/15 00:19:06]

Done.

+    : public testing::Test,
+      public SyncManager::ChangeDelegate {
+ public:
+  virtual void SetUp() OVERRIDE {
+    db_.reset(new sql::Connection);
+    CHECK(db_->OpenInMemory());
+
+    worker_ = new FakeModelWorker(GROUP_UI);
+  }
+
+  MOCK_METHOD4(OnChangesApplied,
+               void(ModelType model_type,
+                    int64 model_version,
+                    const BaseTransaction* trans,
+                    const ImmutableChangeRecordList& changes));
+  MOCK_METHOD1(OnChangesComplete, void(ModelType model_type));
+
+  void OnConfigDone(bool success) {
+    EXPECT_TRUE(success);
+  }
+
+  void VerifyChanges(const ImmutableChangeRecordList& changes) {
+    std::set<int64> deleted;
+    for (size_t i = 0; i < changes.Get().size(); ++i) {
+      const ChangeRecord& change = (changes.Get())[i];
+      EXPECT_EQ(ChangeRecord::ACTION_DELETE, change.action);
+      EXPECT_TRUE(deleted.find(change.id) == deleted.end());
+      deleted.insert(change.id);
+    }
+    EXPECT_TRUE(expected_deletes_ == deleted);
+  }
+
+ protected:

[Nicolas Zea, 2014/04/14 21:36:31]

I'm not sure there's any point to distinguish between public and protected.

[haitaol1, 2014/04/15 00:19:06]

Done.

+  int64 CreateEntry(UserShare* user_share, ModelType type,
+                    const std::string& client_tag) {
+    WriteTransaction trans(FROM_HERE, user_share);
+    ReadNode type_root(&trans);
+    EXPECT_EQ(BaseNode::INIT_OK,
+              type_root.InitByTagLookup(ModelTypeToRootTag(type)));
+
+    WriteNode node(&trans);
+    EXPECT_EQ(WriteNode::INIT_SUCCESS,
+              node.InitUniqueByCreation(type, type_root, client_tag));
+    return node.GetEntry()->GetMetahandle();
+  }
+
+  void InitManager(SyncManager *manager, ModelTypeSet types) {

[Nicolas Zea, 2014/04/14 21:36:31]

nit: SyncManager *manager -> SyncManager* manager (move the asterisk)

[haitaol1, 2014/04/15 00:19:06]

Done.

+    TestInternalComponentsFactory factory(
+        scoped_ptr<syncable::DirectoryBackingStore>(
+            new syncable::TestDirectoryBackingStore("test", db_.get())));
+
+    manager->Init(base::FilePath("test"),

[Nicolas Zea, 2014/04/14 21:36:31]

is this going to leave the database behind after the test is run?

[haitaol1, 2014/04/15 00:19:06]

No, db will be destroyed when test instance is destructed.

+                  MakeWeakHandle(base::WeakPtr<JsEventHandler>()),
+                  "", 0, true, scoped_ptr<HttpPostProviderFactory>().Pass(),
+                  std::vector<scoped_refptr<ModelSafeWorker> >(1,
+                                                               worker_.get()),
+                  NULL, this, SyncCredentials(), "", "", "", &factory,
+                  NULL, scoped_ptr<UnrecoverableErrorHandler>().Pass(),
+                  NULL, NULL);
+    manager->ConfigureSyncer(
+        CONFIGURE_REASON_NEW_CLIENT,
+        types,
+        ModelTypeSet(), ModelTypeSet(), ModelTypeSet(), ModelSafeRoutingInfo(),
+        base::Bind(&SyncRollbackManagerTest::OnConfigDone,
+                   base::Unretained(this), true),
+        base::Bind(&SyncRollbackManagerTest::OnConfigDone,
+                   base::Unretained(this), false));
+  }
+
+  void PrepopulateDb(ModelType type, const std::string& client_tag) {

[Nicolas Zea, 2014/04/14 21:36:31]

Comment for the method.

[haitaol1, 2014/04/15 00:19:06]

Done.

+    SyncBackupManager backup_manager;
+    InitManager(&backup_manager, ModelTypeSet(type));
+    CreateEntry(backup_manager.GetUserShare(), type, client_tag);
+    backup_manager.ShutdownOnSyncThread();
+  }
+
+  bool VerifyEntry(UserShare* user_share, ModelType type,

[Nicolas Zea, 2014/04/14 21:36:31]

pass UserShare by const ref?

Also comment for the method and what it's verifying.

[haitaol1, 2014/04/15 00:19:06]

ReadTransaction doesn't use const share.

+                   const std::string& client_tag) {
+    ReadTransaction trans(FROM_HERE, user_share);
+    ReadNode node(&trans);
+    return BaseNode::INIT_OK == node.InitByClientTagLookup(type, client_tag);
+  }
+
+ protected:

[Nicolas Zea, 2014/04/14 21:36:31]

this section is already within a "protected"

[haitaol1, 2014/04/15 00:19:06]

Done.

+  scoped_ptr<sql::Connection> db_;
+  scoped_refptr<ModelSafeWorker> worker_;
+  std::set<int64> expected_deletes_;
+  base::MessageLoop loop_;    // Needed for WeakHandle
+};
+
+TEST_F(SyncRollbackManagerTest, RollbackBasic) {
+  PrepopulateDb(PREFERENCES, "pref1");
+
+  SyncRollbackManager rollback_manager;
+  InitManager(&rollback_manager, ModelTypeSet(PREFERENCES));
+
+  // Simulate a new entry added during type initialization.
+  int64 new_pref_id =
+      CreateEntry(rollback_manager.GetUserShare(), PREFERENCES, "pref2");
+
+  expected_deletes_.insert(new_pref_id);
+  EXPECT_CALL(*this, OnChangesApplied(_, _, _, _))

[Nicolas Zea, 2014/04/14 21:36:31]

In general it's encouraged to avoid mock logic like this that starts performing
actions and such. It's very easy for this mock logic to become overly
complicated and error-prone.

Could you instead just have a separate ChangeDelegate class that you inform of
the expected behavior? That would also clean up your Test class to not be doing
ChangeDelegate work as well.

[haitaol1, 2014/04/15 00:19:06]

Done.

+      .Times(1)
+      .WillOnce(WithArgs<3>(
+          Invoke(this,&SyncRollbackManagerTest::VerifyChanges)));
+  EXPECT_CALL(*this, OnChangesComplete(_)).Times(1);
+
+  ModelSafeRoutingInfo routing_info;
+  routing_info[PREFERENCES] = GROUP_UI;
+  rollback_manager.StartSyncingNormally(routing_info);
+}
+
+TEST_F(SyncRollbackManagerTest, NoRollbackOfTypesNotBackedUp) {
+  PrepopulateDb(PREFERENCES, "pref1");
+
+  SyncRollbackManager rollback_manager;
+  InitManager(&rollback_manager, ModelTypeSet(PREFERENCES, APPS));
+
+  // Simulate new entry added during type initialization.
+  int64 new_pref_id =
+      CreateEntry(rollback_manager.GetUserShare(), PREFERENCES, "pref2");
+  CreateEntry(rollback_manager.GetUserShare(), APPS, "app1");
+
+  expected_deletes_.insert(new_pref_id);
+  EXPECT_CALL(*this, OnChangesApplied(_, _, _, _))
+      .Times(1)
+      .WillOnce(WithArgs<3>(
+          Invoke(this,&SyncRollbackManagerTest::VerifyChanges)));
+  EXPECT_CALL(*this, OnChangesComplete(_)).Times(1);
+
+  ModelSafeRoutingInfo routing_info;
+  routing_info[PREFERENCES] = GROUP_UI;
+  rollback_manager.StartSyncingNormally(routing_info);
+
+  // APP entry is still valid.
+  EXPECT_TRUE(VerifyEntry(rollback_manager.GetUserShare(), APPS, "app1"));
+}
+
+TEST_F(SyncRollbackManagerTest, BackupDbNotChangedOnAbort) {
+  PrepopulateDb(PREFERENCES, "pref1");
+
+  scoped_ptr<SyncRollbackManager> rollback_manager(
+      new SyncRollbackManager);
+  InitManager(rollback_manager.get(), ModelTypeSet(PREFERENCES));
+
+  // Simulate a new entry added during type initialization.
+  CreateEntry(rollback_manager->GetUserShare(), PREFERENCES, "pref2");
+
+  // Manager was shut down before sync starts.
+  rollback_manager->ShutdownOnSyncThread();
+
+  // Verify new entry was not persisted.
+  rollback_manager.reset(new SyncRollbackManager);
+  InitManager(rollback_manager.get(), ModelTypeSet(PREFERENCES));
+  EXPECT_FALSE(VerifyEntry(rollback_manager->GetUserShare(), PREFERENCES,
+                           "pref2"));
+}
+
+}  // namespace syncer