require 'abstract_unit' ActionController.add_renderer :simon do |says, options| self.content_type = Mime::TEXT self.response_body = "Simon says: #{says}" end class RenderOtherTest < ActionController::TestCase class TestController < ActionController::Base def render_simon_says render :simon => "foo" end end tests TestController def test_using_custom_render_option get :render_simon_says assert_equal "Simon says: foo", @response.body end end