Symfony\Component\EventDispatcher\EventDispatcher::getListeners PHP Method

    public function getListeners($eventName = null)
    {
        if (null !== $eventName) {
            if (!isset($this->sorted[$eventName])) {
                $this->sortListeners($eventName);
            }

            return $this->sorted[$eventName];
        }

        foreach (array_keys($this->listeners) as $eventName) {
            if (!isset($this->sorted[$eventName])) {
                $this->sortListeners($eventName);
            }
        }

        return $this->sorted;
    }

 public function testCookieIsNotUpdatedWithFalseSetCookieOnChange()
 {
     $listener = $this->getLocaleUpdateListener(array('cookie'), false);
     $listener->onLocaleChange($this->getFilterLocaleSwitchEvent(false));
     $addedListeners = $this->dispatcher->getListeners(KernelEvents::RESPONSE);
     $this->assertSame(array(), $addedListeners);
 }