listener3.getPath() >> b.path

        when:
        graph.add(a)
        graph.addListener(listener1)
        graph.add(b)

        then:
        1 * listener1.onDiscovered(graph.root)
        1 * listener1.onDiscovered(a) >> { graph.addListener(listener2); false }
        1 * listener1.onDiscovered(b) >> { graph.addListener(listener3); false }
        1 * listener2.onDiscovered(b)
        1 * listener3.onDiscovered(b)

        when:
        runner.execute(buildAction, buildSessionContext)

        then:
        1 * listenerManager.addListener(listener1)
        1 * listenerManager.addListener(listener2)
        1 * buildOperationListenerManager.addListener(listener1)
        1 * buildOperationListenerManager.addListener(listener2)

        then:
        1 * delegate.execute(buildAction, buildSessionContext)

        then:

    listenable.addListener(earlyListener, directExecutor());

    input.allowGetToComplete.countDown();
    // Now give the get() thread time to finish:
    assertTrue(earlyListener.wasRun.await(1, SECONDS));

    // Now test an additional addListener call, which will be run in-thread:
    RecordingRunnable lateListener = new RecordingRunnable();
    listenable.addListener(lateListener, directExecutor());

        TaskExecutionListener | "taskExecutionListener" | "gradle.addListener"                        | "Gradle.addListener"
        TaskExecutionListener | "taskExecutionListener" | "gradle.taskGraph.addTaskExecutionListener" | "TaskExecutionGraph.addTaskExecutionListener"
        TaskActionListener    | "taskActionListener"    | "gradle.addListener"                        | "Gradle.addListener"
    }

    ListenerCallQueue<Object> queue = new ListenerCallQueue<>();
    queue.addListener(listener1, directExecutor());

    Multiset<Object> counters = ConcurrentHashMultiset.create();
    queue.enqueue(incrementingEvent(counters, listener1, 1));
    queue.enqueue(incrementingEvent(counters, listener1, 2));

    Object listener2 = new Object();
    queue.addListener(listener2, directExecutor());

    ListenerCallQueue<Object> queue = new ListenerCallQueue<>();
    queue.addListener(listener1, directExecutor());

    Multiset<Object> counters = ConcurrentHashMultiset.create();
    queue.enqueue(incrementingEvent(counters, listener1, 1));
    queue.enqueue(incrementingEvent(counters, listener1, 2));

    Object listener2 = new Object();
    queue.addListener(listener2, directExecutor());

		panic(err)
	}

	return ret.verifyOptions, true
}

// AddListener adds a listener to be notified when the CA content changes.
func (c unionCAContent) AddListener(listener Listener) {
	for _, curr := range c {
		curr.AddListener(listener)
	}
}

// AddListener adds a listener to be notified when the CA content changes.
func (c unionCAContent) RunOnce(ctx context.Context) error {

    def "notifies start and progress in registration order, finish in reverse registration order"() {
        given:
        manager.addListener(recordingListener("1"))
        manager.addListener(recordingListener("2"))
        manager.addListener(recordingListener("3"))

        when:
        broadcaster.started(op1, startEvent)
        broadcaster.started(op2, startEvent)

                void onOutput(TestDescriptor testDescriptor, TestOutputEvent outputEvent) {}
            }
            gradle.addListener($listener)
            task broken
        """

        when:

        when:
        daemonScanInfo.notifyOnUnhealthy(notifyAction)

        then:
        1 * listenerManager.addListener({ it instanceof DaemonExpirationListener }) >> { DaemonExpirationListener listener ->
            daemonExpirationListener = listener
        }
        1 * listenerManager.addListener({ it instanceof BuildListener }) >> { BuildListener listener ->
            buildListener = listener
        }

        when: