then:
        1 * event.render(!null) >> { args -> args[0].exception(failure) }
        output.value == 'java.lang.RuntimeException: broken\n{stacktrace}\n'
    }

    def rendersOutputEventWhenInDebugMode() {
        StyledTextOutput output = new TestStyledTextOutput()
        StyledTextOutputBackedRenderer renderer = new StyledTextOutputBackedRenderer(output)
        RenderableOutputEvent event = event(tenAm, 'message')