src/AdvanceEventEmitterTrait.php
public function emit(string $eventName, EventInterface $event = null) : self
    {
        $event = $event ?? new Event();

        foreach ($this->getListeners($eventName) as $listener) {
            call_user_func($listener, $event);

            if (true == $event->isPropagationStopped()) {
                break;
            }
        }

        return $this;
    }
public function emit(string $eventName, EventInterface $event = null) : self
    {
        $event = $event ?? new Event();

        foreach ($this->getListeners($eventName) as $listener) {
            call_user_func($listener, $event);

            if (true == $event->isPropagationStopped()) {
                break;
            }
        }

        return $this;
    }
@param string         $eventName
@param EventInterface $event

@return $this