def "listener can receive task finish events"() {
        def listener = Mock(OperationCompletionListener)
        def provider = Providers.of(listener)
        def success = taskFinishEvent()
        def failure = failedTaskFinishEvent()
        def skipped = skippedTaskFinishEvent()

        when:
        registry.onTaskCompletion(provider)

        then:
        registry.subscriptions.size() == 1
        0 * listener._