diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index 29306668c7b2a..bd76b3f61dd93 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Added TestResponse#binary_content that'll return as a string the data sent through send_data/send_file for testing #500 [Alexey]
+
 * Added @request.env['RAW_POST_DATA'] for people who need access to the data before Ruby's CGI has parsed it #505 [bitsweat]
 
 * Fixed that a default fragment store wan't being set to MemoryStore as intended.
diff --git a/actionpack/lib/action_controller/test_process.rb b/actionpack/lib/action_controller/test_process.rb
index 6fd5249836067..2ab955b6777d9 100644
--- a/actionpack/lib/action_controller/test_process.rb
+++ b/actionpack/lib/action_controller/test_process.rb
@@ -191,6 +191,23 @@ def cookies
       headers['cookie'].inject({}) { |hash, cookie| hash[cookie.name] = cookie; hash }
     end
 
+    # Returns binary content (downloadable file), converted to a String
+    def binary_content
+      raise "Response body is not a Proc: #{body.inspect}" unless body.kind_of?(Proc)
+      require 'stringio'
+
+      sio = StringIO.new
+
+      begin 
+        $stdout = sio
+        body.call
+      ensure
+        $stdout = STDOUT
+      end
+
+      sio.rewind
+      sio.read
+    end
 end
 
   class TestSession #:nodoc: