Refactor PickleIterator.

chrome/browser/extensions/api/messaging/native_message_process_host_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/bind.h"
 #include "base/file_util.h"
 #include "base/files/file.h"
 #include "base/files/file_path.h"
 #include "base/files/scoped_file.h"
 #include "base/files/scoped_temp_dir.h"
@@ skipping 124 matching lines @@
 
   virtual void CloseChannel(int port_id,
                             const std::string& error_message) OVERRIDE {
     channel_closed_ = true;
     if (run_loop_)
       run_loop_->Quit();
   }
 
  protected:
   std::string FormatMessage(const std::string& message) {
-    Pickle pickle;
-    pickle.WriteString(message);
-    return std::string(const_cast<const Pickle*>(&pickle)->payload(),
-                       pickle.payload_size());
+    uint32_t length = message.length();
+    return std::string(reinterpret_cast<char*>(&length), 4).append(message);

[jar (doing other things), 2014/05/22 02:51:00]

The original code is confusing for other reasons... like why would you use const
cast to add const-ness?

...but why can't that code still work?.... and why are you providing a separate
implementation of the writing of a string (message) here? Why isn't the other
code still functional?

[halyavin, 2014/05/22 04:05:25]

I made Pickle payload size aligned to 4 bytes and hence the resulting string had
extra zeros at the end.

[jar (doing other things), 2014/05/23 21:22:04]

Yes... SGTM.  thx.

   }
 
   base::FilePath CreateTempFileWithMessage(const std::string& message) {
     base::FilePath filename;
     if (!base::CreateTemporaryFileInDir(temp_dir_.path(), &filename))
       return base::FilePath();
 
     std::string message_with_header = FormatMessage(message);
     int bytes_written = base::WriteFile(
         filename, message_with_header.data(), message_with_header.size());
@@ skipping 155 matching lines @@
       ScopedTestNativeMessagingHost::kHostName, 0, false);
   ASSERT_TRUE(native_message_process_host_.get());
   run_loop_.reset(new base::RunLoop());
   run_loop_->Run();
 
   // The host should fail to start.
   ASSERT_TRUE(channel_closed_);
 }
 
 }  // namespace extensions