1 files changed, 47 insertions, 13 deletions

diff --git a/actionpack/lib/action_dispatch/http/response.rb b/actionpack/lib/action_dispatch/http/response.rb
index 0f808ac9cf..5247e61a23 100644
--- a/actionpack/lib/action_dispatch/http/response.rb
+++ b/actionpack/lib/action_dispatch/http/response.rb
@@ -1,4 +1,3 @@
-require 'digest/md5'
 require 'active_support/core_ext/class/attribute_accessors'
 require 'monitor'
 
@@ -32,10 +31,17 @@ module ActionDispatch # :nodoc:
   #    end
   #  end
   class Response
-    attr_accessor :request, :header
+    # The request that the response is responding to.
+    attr_accessor :request
+
+    # The HTTP status code.
     attr_reader :status
+
     attr_writer :sending_file
 
+    # Get and set headers for this response.
+    attr_accessor :header
+
     alias_method :headers=, :header=
     alias_method :headers,  :header
 
@@ -50,12 +56,16 @@ module ActionDispatch # :nodoc:
     # If a character set has been defined for this response (see charset=) then
     # the character set information will also be included in the content type
     # information.
-    attr_accessor :charset
     attr_reader   :content_type
 
+    # The charset of the response. HTML wants to know the encoding of the
+    # content you're giving them, so we need to send that along.
+    attr_accessor :charset
+
     CONTENT_TYPE = "Content-Type".freeze
     SET_COOKIE   = "Set-Cookie".freeze
     LOCATION     = "Location".freeze
+    NO_CONTENT_CODES = [204, 304]
 
     cattr_accessor(:default_charset) { "utf-8" }
     cattr_accessor(:default_headers)
@@ -93,6 +103,7 @@ module ActionDispatch # :nodoc:
       end
     end
 
+    # The underlying body, as a streamable object.
     attr_reader :stream
 
     def initialize(status = 200, header = {}, body = [])
@@ -137,32 +148,42 @@ module ActionDispatch # :nodoc:
       @committed
     end
 
+    # Sets the HTTP status code.
     def status=(status)
       @status = Rack::Utils.status_code(status)
     end
 
+    # Sets the HTTP content type.
     def content_type=(content_type)
       @content_type = content_type.to_s
     end
 
-    # The response code of the request
+    # The response code of the request.
     def response_code
       @status
     end
 
-    # Returns a String to ensure compatibility with Net::HTTPResponse
+    # Returns a string to ensure compatibility with <tt>Net::HTTPResponse</tt>.
     def code
       @status.to_s
     end
 
+    # Returns the corresponding message for the current HTTP status code:
+    #
+    #   response.status = 200
+    #   response.message # => "OK"
+    #
+    #   response.status = 404
+    #   response.message # => "Not Found"
+    #
     def message
       Rack::Utils::HTTP_STATUS_CODES[@status]
     end
     alias_method :status_message, :message
 
-    def respond_to?(method)
-      if method.to_sym == :to_path
-        stream.respond_to?(:to_path)
+    def respond_to?(method, include_private = false)
+      if method.to_s == 'to_path'
+        stream.respond_to?(method)
       else
         super
       end
@@ -172,6 +193,8 @@ module ActionDispatch # :nodoc:
       stream.to_path
     end
 
+    # Returns the content of the response as a string. This contains the contents
+    # of any calls to <tt>render</tt>.
     def body
       strings = []
       each { |part| strings << part.to_s }
@@ -180,13 +203,16 @@ module ActionDispatch # :nodoc:
 
     EMPTY = " "
 
+    # Allows you to manually set or override the response body.
     def body=(body)
       @blank = true if body == EMPTY
 
       if body.respond_to?(:to_path)
         @stream = body
       else
-        @stream = build_buffer self, munge_body_object(body)
+        synchronize do
+          @stream = build_buffer self, munge_body_object(body)
+        end
       end
     end
 
@@ -204,11 +230,13 @@ module ActionDispatch # :nodoc:
       ::Rack::Utils.delete_cookie_header!(header, key, value)
     end
 
+    # The location header we'll be responding with.
     def location
       headers[LOCATION]
     end
     alias_method :redirect_url, :location
 
+    # Sets the location header we'll be responding with.
     def location=(url)
       headers[LOCATION] = url
     end
@@ -217,11 +245,13 @@ module ActionDispatch # :nodoc:
       stream.close if stream.respond_to?(:close)
     end
 
+    # Turns the Response into a Rack-compatible array of the status, headers,
+    # and body.
     def to_a
       rack_response @status, @header.to_hash
     end
     alias prepare! to_a
-    alias to_ary   to_a # For implicit splat on 1.9.2
+    alias to_ary   to_a
 
     # Returns the response cookies, converted to a Hash of (name => value) pairs
     #
@@ -260,21 +290,25 @@ module ActionDispatch # :nodoc:
       return if headers[CONTENT_TYPE].present?
 
       @content_type ||= Mime::HTML
-      @charset      ||= self.class.default_charset
+      @charset      ||= self.class.default_charset unless @charset == false
 
       type = @content_type.to_s.dup
-      type << "; charset=#{@charset}" unless @sending_file
+      type << "; charset=#{@charset}" if append_charset?
 
       headers[CONTENT_TYPE] = type
     end
 
+    def append_charset?
+      !@sending_file && @charset != false
+    end
+
     def rack_response(status, header)
       assign_default_content_type_and_charset!(header)
       handle_conditional_get!
 
       header[SET_COOKIE] = header[SET_COOKIE].join("\n") if header[SET_COOKIE].respond_to?(:join)
 
-      if [204, 304].include?(@status)
+      if NO_CONTENT_CODES.include?(@status)
         header.delete CONTENT_TYPE
         [status, header, []]
       else