assert_template (ActionController::Assertions::ResponseAssertions)

    # File lib/action_controller/assertions/response_assertions.rb, line 88
          def assert_template(expected = nil, message=nil)
            clean_backtrace do
              rendered = @response.rendered_template.to_s
              msg = build_message(message, "expecting <?> but rendering with <?>", expected, rendered)
              assert_block(msg) do
                if expected.nil?
                  @response.rendered_template.blank?
                else
                  rendered.to_s.match(expected)
                end
              end
            end
          end