Extract testing utility TestGetContentCallback.

chrome/browser/google_apis/fake_drive_service_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 "chrome/browser/google_apis/fake_drive_service.h"
 
 #include <string>
 #include <vector>
 
 #include "base/file_util.h"
@@ skipping 73 matching lines @@
         test_util::CreateCopyResultCallback(&error, &about_resource));
     message_loop_.RunUntilIdle();
     return about_resource->largest_change_id();
   }
 
   MessageLoopForUI message_loop_;
   content::TestBrowserThread ui_thread_;
   FakeDriveService fake_service_;
 };
 
-void AppendGetContentCallbackResult(
-    std::vector<std::string>* values,
-    GDataErrorCode error,
-    scoped_ptr<std::string> content) {
-  DCHECK_EQ(error, HTTP_SUCCESS);  // Should always HTTP_SUCCESS.
-  values->push_back(*content);
-}
-
 void AppendProgressCallbackResult(std::vector<int64>* values, int64 progress) {
   values->push_back(progress);
 }
 
 TEST_F(FakeDriveServiceTest, GetAllResourceList) {
   ASSERT_TRUE(fake_service_.LoadResourceListForWapi(
       "chromeos/gdata/root_feed.json"));
 
   GDataErrorCode error = GDATA_OTHER_ERROR;
   scoped_ptr<ResourceList> resource_list;
@@ skipping 745 matching lines @@
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 
   std::vector<test_util::ProgressInfo> download_progress_values;
 
   const GURL kContentUrl("https://file_content_url/");
   const base::FilePath kOutputFilePath =
       temp_dir.path().AppendASCII("whatever.txt");
   GDataErrorCode error = GDATA_OTHER_ERROR;
   base::FilePath output_file_path;
-  std::vector<std::string> content_buffer;
+  test_util::TestGetContentCallback get_content_callback;
   fake_service_.DownloadFile(
       base::FilePath::FromUTF8Unsafe("/drive/whatever.txt"),  // virtual path
       kOutputFilePath,
       kContentUrl,
       test_util::CreateCopyResultCallback(&error, &output_file_path),
-      base::Bind(&AppendGetContentCallbackResult, &content_buffer),
+      get_content_callback.callback(),
       base::Bind(&test_util::AppendProgressCallbackResult,
                  &download_progress_values));
   message_loop_.RunUntilIdle();
 
   EXPECT_EQ(HTTP_SUCCESS, error);
   EXPECT_EQ(output_file_path, kOutputFilePath);
   std::string content;
   ASSERT_TRUE(file_util::ReadFileToString(output_file_path, &content));
   // The content is "x"s of the file size specified in root_feed.json.
   EXPECT_EQ("xxxxxxxxxx", content);
   ASSERT_TRUE(!download_progress_values.empty());
   EXPECT_TRUE(base::STLIsSorted(download_progress_values));
   EXPECT_GE(download_progress_values.front().first, 0);
   EXPECT_LE(download_progress_values.back().first, 10);
-
-  std::string concatenated_content;
-  for (size_t i = 0; i < content_buffer.size(); ++i) {
-    concatenated_content += content_buffer[i];
-  }
-  EXPECT_EQ(content, concatenated_content);
+  EXPECT_EQ(content, get_content_callback.GetConcatenatedData());
 }
 
 TEST_F(FakeDriveServiceTest, DownloadFile_NonexistingFile) {
   ASSERT_TRUE(fake_service_.LoadResourceListForWapi(
       "chromeos/gdata/root_feed.json"));
 
   base::ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
 
   const GURL kContentUrl("https://non_existing_content_url/");
@@ skipping 1104 matching lines @@
       test_util::CreateCopyResultCallback(&error, &resource_entry));
   message_loop_.RunUntilIdle();
 
   EXPECT_EQ(GDATA_NO_CONNECTION, error);
   EXPECT_FALSE(resource_entry);
 }
 
 }  // namespace
 
 }  // namespace google_apis