making sure respond_to? works properly

actionpack/lib/action_dispatch/http/upload.rb

@@ -13,7 +13,12 @@ module ActionDispatch
         raise(ArgumentError, ':tempfile is required') unless @tempfile
       end
 
+      def respond_to?(name)
+        super || @tempfile.respond_to?(name)
+      end
+
       def method_missing(name, *args, &block)
+        return super unless respond_to?(name)
         @tempfile.send(name, *args, &block)
       end
     end

actionpack/test/dispatch/uploaded_file_test.rb

@@ -45,5 +45,20 @@ module ActionDispatch
       uf = Http::UploadedFile.new(:tempfile => tf.new)
       assert_equal('thunderhorse', uf.tenderlove { 'thunderhorse' })
     end
+
+    def test_delegate_respects_respond_to?
+      tf = Class.new { def tenderlove; yield end; private :tenderlove }
+      uf = Http::UploadedFile.new(:tempfile => tf.new)
+      assert_raises(NoMethodError) do
+        uf.tenderlove
+      end
+    end
+
+    def test_respond_to?
+      tf = Class.new { def tenderlove; yield end }
+      uf = Http::UploadedFile.new(:tempfile => tf.new)
+      assert uf.respond_to?(:headers), 'responds to headers'
+      assert uf.respond_to?(:tenderlove), 'responds to tenderlove'
+    end
   end
 end