Moved JsonPrefStore to use SequencedWorkerPool

chrome/common/json_pref_store_unittest.cc

 // Copyright (c) 2012 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/file_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/message_loop.h"
-#include "base/message_loop_proxy.h"
 #include "base/path_service.h"
 #include "base/scoped_temp_dir.h"
 #include "base/string_number_conversions.h"
 #include "base/string_util.h"
+#include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/json_pref_store.h"
 #include "chrome/common/pref_names.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 class MockPrefStoreObserver : public PrefStore::Observer {
  public:
   MOCK_METHOD1(OnPrefValueChanged, void (const std::string&));
   MOCK_METHOD1(OnInitializationCompleted, void (bool));
 };
 
 class MockReadErrorDelegate : public PersistentPrefStore::ReadErrorDelegate {
  public:
   MOCK_METHOD1(OnError, void(PersistentPrefStore::PrefReadError));
 };
 
 }  // namespace
 
 class JsonPrefStoreTest : public testing::Test {
  protected:
-  virtual void SetUp() {
-    message_loop_proxy_ = base::MessageLoopProxy::current();
+  virtual void SetUp() OVERRIDE {
+    blocking_pool_ = new base::SequencedWorkerPool(3, "TestBlocking");
 
     ASSERT_TRUE(temp_dir_.CreateUniqueTempDir());
 
     ASSERT_TRUE(PathService::Get(chrome::DIR_TEST_DATA, &data_dir_));
     data_dir_ = data_dir_.AppendASCII("pref_service");
     ASSERT_TRUE(file_util::PathExists(data_dir_));
   }
 
+  virtual void TearDown() OVERRIDE {
+    blocking_pool_->Shutdown();
+  }
+
   // The path to temporary directory used to contain the test operations.
   ScopedTempDir temp_dir_;
   // The path to the directory where the test data is stored.
   FilePath data_dir_;
-  // A message loop that we can use as the file thread message loop.
+  // A message loop that we need for timers.
   MessageLoop message_loop_;
-  scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
+  // A blocking pool that we can use for file operations.
+  scoped_refptr<base::SequencedWorkerPool> blocking_pool_;
 };
 
 // Test fallback behavior for a nonexistent file.
 TEST_F(JsonPrefStoreTest, NonExistentFile) {
   FilePath bogus_input_file = data_dir_.AppendASCII("read.txt");
   ASSERT_FALSE(file_util::PathExists(bogus_input_file));
   scoped_refptr<JsonPrefStore> pref_store =
-      new JsonPrefStore(bogus_input_file, message_loop_proxy_.get());
+      JsonPrefStore::Create(
+          bogus_input_file,
+          JsonPrefStore::GetTaskRunnerForFile(bogus_input_file,
+                                              blocking_pool_));
   EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_NO_FILE,
             pref_store->ReadPrefs());
   EXPECT_FALSE(pref_store->ReadOnly());
 }
 
 // Test fallback behavior for an invalid file.
 TEST_F(JsonPrefStoreTest, InvalidFile) {
   FilePath invalid_file_original = data_dir_.AppendASCII("invalid.json");
   FilePath invalid_file = temp_dir_.path().AppendASCII("invalid.json");
   ASSERT_TRUE(file_util::CopyFile(invalid_file_original, invalid_file));
   scoped_refptr<JsonPrefStore> pref_store =
-      new JsonPrefStore(invalid_file, message_loop_proxy_.get());
+      JsonPrefStore::Create(
+          invalid_file,
+          JsonPrefStore::GetTaskRunnerForFile(invalid_file, blocking_pool_));
   EXPECT_EQ(PersistentPrefStore::PREF_READ_ERROR_JSON_PARSE,
             pref_store->ReadPrefs());
   EXPECT_FALSE(pref_store->ReadOnly());
 
   // The file should have been moved aside.
   EXPECT_FALSE(file_util::PathExists(invalid_file));
   FilePath moved_aside = temp_dir_.path().AppendASCII("invalid.bad");
   EXPECT_TRUE(file_util::PathExists(moved_aside));
   EXPECT_TRUE(file_util::TextContentsEqual(invalid_file_original,
                                            moved_aside));
 }
 
 // This function is used to avoid code duplication while testing synchronous and
 // asynchronous version of the JsonPrefStore loading.
-void RunBasicJsonPrefStoreTest(JsonPrefStore *pref_store,
+void RunBasicJsonPrefStoreTest(base::SequencedWorkerPool* blocking_pool,

[akalin, 2012/10/19 02:00:51]

looks like you don't actually use the blocking pool in this test?  If you can
remove this, then I think you can just use a regular message loop proxy for all
the tests in this file.

(Unless you want to explicitly test behavior with BlockingPools here?  If so,
add a comment.)

+                               JsonPrefStore *pref_store,

[akalin, 2012/10/19 02:00:51]

' *' -> '* '

                                const FilePath& output_file,
                                const FilePath& golden_output_file) {
   const char kNewWindowsInTabs[] = "tabs.new_windows_in_tabs";
   const char kMaxTabs[] = "tabs.max_tabs";
   const char kLongIntPref[] = "long_int.pref";
 
   std::string cnn("http://www.cnn.com");
 
   const Value* actual;
   EXPECT_EQ(PrefStore::READ_OK,
@@ skipping 44 matching lines @@
                           base::Int64ToString(214748364842LL)));
   EXPECT_EQ(PrefStore::READ_OK, pref_store->GetValue(kLongIntPref, &actual));
   EXPECT_TRUE(actual->GetAsString(&string_value));
   int64 value;
   base::StringToInt64(string_value, &value);
   EXPECT_EQ(214748364842LL, value);
 
   // Serialize and compare to expected output.
   ASSERT_TRUE(file_util::PathExists(golden_output_file));
   pref_store->CommitPendingWrite();
-  MessageLoop::current()->RunAllPending();
+  blocking_pool->FlushForTesting();
   EXPECT_TRUE(file_util::TextContentsEqual(golden_output_file, output_file));
   ASSERT_TRUE(file_util::Delete(output_file, false));
 }
 
 TEST_F(JsonPrefStoreTest, Basic) {
   ASSERT_TRUE(file_util::CopyFile(data_dir_.AppendASCII("read.json"),
                                   temp_dir_.path().AppendASCII("write.json")));
 
   // Test that the persistent value can be loaded.
   FilePath input_file = temp_dir_.path().AppendASCII("write.json");
   ASSERT_TRUE(file_util::PathExists(input_file));
   scoped_refptr<JsonPrefStore> pref_store =
-      new JsonPrefStore(input_file, message_loop_proxy_.get());
+      JsonPrefStore::Create(
+          input_file,
+          JsonPrefStore::GetTaskRunnerForFile(input_file, blocking_pool_));
   ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE, pref_store->ReadPrefs());
   ASSERT_FALSE(pref_store->ReadOnly());
 
   // The JSON file looks like this:
   // {
   //   "homepage": "http://www.cnn.com",
   //   "some_directory": "/usr/local/",
   //   "tabs": {
   //     "new_windows_in_tabs": true,
   //     "max_tabs": 20
   //   }
   // }
 
-  RunBasicJsonPrefStoreTest(pref_store,
+  RunBasicJsonPrefStoreTest(blocking_pool_.get(),
+                            pref_store,
                             input_file,
                             data_dir_.AppendASCII("write.golden.json"));
 }
 
 TEST_F(JsonPrefStoreTest, BasicAsync) {
   ASSERT_TRUE(file_util::CopyFile(data_dir_.AppendASCII("read.json"),
                                   temp_dir_.path().AppendASCII("write.json")));
 
   // Test that the persistent value can be loaded.
   FilePath input_file = temp_dir_.path().AppendASCII("write.json");
   ASSERT_TRUE(file_util::PathExists(input_file));
   scoped_refptr<JsonPrefStore> pref_store =
-      new JsonPrefStore(input_file, message_loop_proxy_.get());
+      JsonPrefStore::Create(
+          input_file,
+          JsonPrefStore::GetTaskRunnerForFile(input_file, blocking_pool_));
 
-  MockPrefStoreObserver mock_observer;
-  pref_store->AddObserver(&mock_observer);
+  {
+    MockPrefStoreObserver mock_observer;
+    pref_store->AddObserver(&mock_observer);
 
-  MockReadErrorDelegate *mock_error_delegate = new MockReadErrorDelegate;
-  pref_store->ReadPrefsAsync(mock_error_delegate);
+    MockReadErrorDelegate *mock_error_delegate = new MockReadErrorDelegate;

[akalin, 2012/10/19 02:00:51]

' *' -> '* '

[zel, 2012/10/19 18:45:07]

Done.

+    pref_store->ReadPrefsAsync(mock_error_delegate);
 
-  EXPECT_CALL(mock_observer, OnInitializationCompleted(true)).Times(1);
-  EXPECT_CALL(*mock_error_delegate,
-              OnError(PersistentPrefStore::PREF_READ_ERROR_NONE)).Times(0);
-  message_loop_.RunAllPending();
-  pref_store->RemoveObserver(&mock_observer);
+    EXPECT_CALL(mock_observer, OnInitializationCompleted(true)).Times(1);
+    EXPECT_CALL(*mock_error_delegate,
+                OnError(PersistentPrefStore::PREF_READ_ERROR_NONE)).Times(0);
+    blocking_pool_->FlushForTesting();
+    message_loop_.RunAllPending();
+    pref_store->RemoveObserver(&mock_observer);
 
-  ASSERT_FALSE(pref_store->ReadOnly());
+    ASSERT_FALSE(pref_store->ReadOnly());
+  }
 
   // The JSON file looks like this:
   // {
   //   "homepage": "http://www.cnn.com",
   //   "some_directory": "/usr/local/",
   //   "tabs": {
   //     "new_windows_in_tabs": true,
   //     "max_tabs": 20
   //   }
   // }
 
-  RunBasicJsonPrefStoreTest(pref_store,
+  RunBasicJsonPrefStoreTest(blocking_pool_.get(),
+                            pref_store,
                             input_file,
                             data_dir_.AppendASCII("write.golden.json"));
 }
 
 // Tests asynchronous reading of the file when there is no file.
 TEST_F(JsonPrefStoreTest, AsyncNonExistingFile) {
   FilePath bogus_input_file = data_dir_.AppendASCII("read.txt");
   ASSERT_FALSE(file_util::PathExists(bogus_input_file));
   scoped_refptr<JsonPrefStore> pref_store =
-      new JsonPrefStore(bogus_input_file, message_loop_proxy_.get());
+      JsonPrefStore::Create(
+          bogus_input_file,
+          JsonPrefStore::GetTaskRunnerForFile(bogus_input_file,
+                                              blocking_pool_));
   MockPrefStoreObserver mock_observer;
   pref_store->AddObserver(&mock_observer);
 
   MockReadErrorDelegate *mock_error_delegate = new MockReadErrorDelegate;
   pref_store->ReadPrefsAsync(mock_error_delegate);
 
   EXPECT_CALL(mock_observer, OnInitializationCompleted(true)).Times(1);
   EXPECT_CALL(*mock_error_delegate,
               OnError(PersistentPrefStore::PREF_READ_ERROR_NO_FILE)).Times(1);
+  blocking_pool_->FlushForTesting();
   message_loop_.RunAllPending();
   pref_store->RemoveObserver(&mock_observer);
 
   EXPECT_FALSE(pref_store->ReadOnly());
 }
 
 TEST_F(JsonPrefStoreTest, NeedsEmptyValue) {
   FilePath pref_file = temp_dir_.path().AppendASCII("write.json");
 
   ASSERT_TRUE(file_util::CopyFile(
       data_dir_.AppendASCII("read.need_empty_value.json"),
       pref_file));
 
   // Test that the persistent value can be loaded.
   ASSERT_TRUE(file_util::PathExists(pref_file));
   scoped_refptr<JsonPrefStore> pref_store =
-      new JsonPrefStore(pref_file, message_loop_proxy_.get());
+      JsonPrefStore::Create(
+          pref_file,
+          JsonPrefStore::GetTaskRunnerForFile(pref_file, blocking_pool_));
   ASSERT_EQ(PersistentPrefStore::PREF_READ_ERROR_NONE, pref_store->ReadPrefs());
   ASSERT_FALSE(pref_store->ReadOnly());
 
   // The JSON file looks like this:
   // {
   //   "list": [ 1 ],
   //   "list_needs_empty_value": [ 2 ],
   //   "dict": {
   //     "dummy": true,
   //   },
   //   "dict_needs_empty_value": {
   //     "dummy": true,
   //   },
   // }
 
   // Set flag to preserve empty values for the following keys.
   pref_store->MarkNeedsEmptyValue("list_needs_empty_value");
   pref_store->MarkNeedsEmptyValue("dict_needs_empty_value");
 
   // Set all keys to empty values.
   pref_store->SetValue("list", new base::ListValue);
   pref_store->SetValue("list_needs_empty_value", new base::ListValue);
   pref_store->SetValue("dict", new base::DictionaryValue);
   pref_store->SetValue("dict_needs_empty_value", new base::DictionaryValue);
 
   // Write to file.
   pref_store->CommitPendingWrite();
-  MessageLoop::current()->RunAllPending();
+  blocking_pool_->FlushForTesting();
 
   // Compare to expected output.
   FilePath golden_output_file =
       data_dir_.AppendASCII("write.golden.need_empty_value.json");
   ASSERT_TRUE(file_util::PathExists(golden_output_file));
   EXPECT_TRUE(file_util::TextContentsEqual(golden_output_file, pref_file));
 }