Add callback list to PrefModelAssociator after sync data is loaded

components/syncable_prefs/pref_service_syncable_unittest.cc

Index: components/syncable_prefs/pref_service_syncable_unittest.cc
diff --git a/components/syncable_prefs/pref_service_syncable_unittest.cc b/components/syncable_prefs/pref_service_syncable_unittest.cc
index 5aaa09616db396c3a53545ddeb412651e6ea4e59..b888ef25e0e52e801f9efb93f8b8328525f69055 100644
--- a/components/syncable_prefs/pref_service_syncable_unittest.cc
+++ b/components/syncable_prefs/pref_service_syncable_unittest.cc
@@ -122,6 +122,7 @@ class PrefServiceSyncableTest : public testing::Test {
         prefs_.GetSyncableService(syncer::PREFERENCES));
     ASSERT_TRUE(pref_sync_service_);
     next_pref_remote_sync_node_id_ = 0;

[Bernhard Bauer, 2016/07/13 08:31:52]

This is not necessary, BTW (each test gets a new fixture insteance).

[lshang, 2016/07/14 01:29:03]

Done.

+    callback_test_num = 0;

[Bernhard Bauer, 2016/07/13 08:31:52]

I would initialize this in the constructor.

[lshang, 2016/07/14 01:29:04]

Done. Also added an underscore at the end of this variable's name since it's a
member of the class.

Oh this is deleted later since I moved it to the anonymous namespace.

   }
 
   syncer::SyncChange MakeRemoteChange(int64_t id,
@@ -204,6 +205,8 @@ class PrefServiceSyncableTest : public testing::Test {
     return pref_sync_service_->IsPrefSynced(pref_name);
   }
 
+  void CallbackFunc() { callback_test_num += 1; }

[Bernhard Bauer, 2016/07/13 08:31:52]

Nit: you could use ++.

[lshang, 2016/07/14 01:29:03]

Done.

+
   PrefService* GetPrefs() { return &prefs_; }
   TestingPrefServiceSyncable* GetTestingPrefService() { return &prefs_; }
 
@@ -218,6 +221,8 @@ class PrefServiceSyncableTest : public testing::Test {
   base::MessageLoop loop_;
 
   int next_pref_remote_sync_node_id_;
+
+  int callback_test_num;

[Bernhard Bauer, 2016/07/13 08:31:52]

Nit: |num_callbacks|?

Alternatively, you could use a static function (in an anonymous namespace) that
takes an int* and increments it, and then bind it with the address of a variable
on the stack. That way, you don't need to have any state in the fixture.

[lshang, 2016/07/14 01:29:04]

Done. The alternative is really cool!

 };
 
 TEST_F(PrefServiceSyncableTest, CreatePrefSyncData) {
@@ -555,6 +560,15 @@ TEST_F(PrefServiceSyncableTest, DeletePreference) {
   EXPECT_TRUE(pref->IsDefaultValue());
 }
 
+TEST_F(PrefServiceSyncableTest, RegisterMergeDataFinishedCallback) {
+  EXPECT_EQ(callback_test_num, 0);

[Bernhard Bauer, 2016/07/13 08:31:52]

The expected value goes first, for nicer error messages in case of failure.

[lshang, 2016/07/14 01:29:03]

Done.

+  prefs_.RegisterMergeDataFinishedCallback(base::Bind(
+      &PrefServiceSyncableTest::CallbackFunc, base::Unretained(this)));
+  EXPECT_EQ(callback_test_num, 0);
+  InitWithNoSyncData();
+  EXPECT_EQ(callback_test_num, 1);
+}
+
 }  // namespace
 
 }  // namespace syncable_prefs