when:
        logger.started()

        then:
        IllegalStateException e = thrown()
        e.message == 'This operation (logger - op) has already been started.'
    }

    def cannotStartAfterComplete() {
        def logger = factory.newOperation('logger')
        logger.description = 'op'
        logger.started()
        logger.completed()

        when:
        logger.started()