Update multipart tests to expose (another) bug in Rack's multipart parser

actionpack/lib/action_controller.rb

@@ -33,6 +33,7 @@ end
 
 gem 'rack', '>= 0.9.0'
 require 'rack'
+require 'action_controller/rack_ext'
 
 module ActionController
   # TODO: Review explicit to see if they will automatically be handled by

actionpack/lib/action_controller/integration.rb

@@ -2,17 +2,6 @@ require 'stringio'
 require 'uri'
 require 'active_support/test_case'
 
-# Monkey patch Rack::Lint to support rewind
-module Rack
-  class Lint
-    class InputWrapper
-      def rewind
-        @input.rewind
-      end
-    end
-  end
-end
-
 module ActionController
   module Integration #:nodoc:
     # An integration Session instance represents a set of requests and responses

actionpack/lib/action_controller/middleware_stack.rb

@@ -32,6 +32,8 @@ module ActionController
         else
           @klass.to_s.constantize
         end
+      rescue NameError
+        @klass
       end
 
       def active?

actionpack/lib/action_controller/rack_ext.rb

@@ -0,0 +1,22 @@
+module Rack
+  module Utils
+    module Multipart
+      class << self
+        def parse_multipart_with_rewind(env)
+          result = parse_multipart_without_rewind(env)
+
+          begin
+            env['rack.input'].rewind if env['rack.input'].respond_to?(:rewind)
+          rescue Errno::ESPIPE
+            # Handles exceptions raised by input streams that cannot be rewound
+            # such as when using plain CGI under Apache
+          end
+
+          result
+        end
+
+        alias_method_chain :parse_multipart, :rewind
+      end
+    end
+  end
+end

actionpack/lib/action_controller/rewindable_input.rb

@@ -15,15 +15,19 @@ module ActionController
         @io.rewind
       end
 
+      def string
+        @string
+      end
+
       def method_missing(method, *args, &block)
         @io.send(method, *args, &block)
       end
 
       private
         def read_original_io
-          unless @str
-            @str = @io.read
-            @io = StringIO.new(@str)
+          unless @string
+            @string = @io.read
+            @io = StringIO.new(@string)
           end
         end
     end

actionpack/test/controller/request/multipart_params_parsing_test.rb

@@ -200,7 +200,7 @@ class MultipartParamsParsingTest < ActionController::IntegrationTest
     def with_muck_middleware
       original_middleware = ActionController::Dispatcher.middleware
       middleware = original_middleware.dup
-      middleware.use MuckMiddleware
+      middleware.insert_after ActionController::RewindableInput, MuckMiddleware
       ActionController::Dispatcher.middleware = middleware
       yield
       ActionController::Dispatcher.middleware = original_middleware

actionpack/test/controller/request/url_encoded_params_parsing_test.rb

@@ -183,7 +183,7 @@ class UrlEncodedParamsParsingTest < ActionController::IntegrationTest
     def with_muck_middleware
       original_middleware = ActionController::Dispatcher.middleware
       middleware = original_middleware.dup
-      middleware.use MuckMiddleware
+      middleware.insert_after ActionController::RewindableInput, MuckMiddleware
       ActionController::Dispatcher.middleware = middleware
       yield
       ActionController::Dispatcher.middleware = original_middleware