private final StandardOutputRedirector.OutputListener stdOutListener = Mock()
    private final StandardOutputRedirector.OutputListener stdErrListener = Mock()

    def startAndStopDoesNothingWhenNothingRedirected() {
        when:
        redirector.start()
        System.out.println('this is stdout')
        System.err.println('this is stderr')
        redirector.stop()

        then: