ContainerAwareEventDispatcherTest.php

<?php

namespace Drupal\Tests\Component\EventDispatcher;

use Drupal\Component\EventDispatcher\ContainerAwareEventDispatcher;
use PHPUnit\Framework\TestCase;
use Symfony\Component\DependencyInjection\Container;
use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\EventDispatcher\Event as SymfonyEvent;
use Symfony\Component\EventDispatcher\GenericEvent;
use Drupal\Component\EventDispatcher\Event;
use Symfony\Bridge\PhpUnit\ExpectDeprecationTrait;

/**
 * Unit tests for the ContainerAwareEventDispatcher.
 *
 * NOTE: Most of this code is a literal copy of Symfony 3.4's
 * Symfony\Component\EventDispatcher\Tests\AbstractEventDispatcherTest.
 *
 * This file does NOT follow Drupal coding standards, so as to simplify future
 * synchronizations.
 *
 * @group EventDispatcher
 */
class ContainerAwareEventDispatcherTest extends TestCase {
    use ExpectDeprecationTrait;
    
    /* Some pseudo events */
    const PREFOO = 'pre.foo';
    const POSTFOO = 'post.foo';
    const PREBAR = 'pre.bar';
    const POSTBAR = 'post.bar';
    
    /**
     * @var \Symfony\Component\EventDispatcher\EventDispatcher
     */
    private $dispatcher;
    private $listener;
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        $this->dispatcher = $this->createEventDispatcher();
        $this->listener = new TestEventListener();
    }
    
    /**
     * {@inheritdoc}
     */
    protected function tearDown() : void {
        $this->dispatcher = NULL;
        $this->listener = NULL;
    }
    protected function createEventDispatcher() {
        $container = new Container();
        return new ContainerAwareEventDispatcher($container);
    }
    public function testGetListenersWithCallables() {
        // When passing in callables exclusively as listeners into the event
        // dispatcher constructor, the event dispatcher must not attempt to
        // resolve any services.
        $container = $this->getMockBuilder(ContainerInterface::class)
            ->getMock();
        $container->expects($this->never())
            ->method($this->anything());
        $firstListener = new CallableClass();
        $secondListener = function () {
        };
        $thirdListener = [
            new TestEventListener(),
            'preFoo',
        ];
        $listeners = [
            'test_event' => [
                0 => [
                    [
                        'callable' => $firstListener,
                    ],
                    [
                        'callable' => $secondListener,
                    ],
                    [
                        'callable' => $thirdListener,
                    ],
                ],
            ],
        ];
        $dispatcher = new ContainerAwareEventDispatcher($container, $listeners);
        $actualListeners = $dispatcher->getListeners();
        $expectedListeners = [
            'test_event' => [
                $firstListener,
                $secondListener,
                $thirdListener,
            ],
        ];
        $this->assertSame($expectedListeners, $actualListeners);
    }
    public function testDispatchWithCallables() {
        // When passing in callables exclusively as listeners into the event
        // dispatcher constructor, the event dispatcher must not attempt to
        // resolve any services.
        $container = $this->getMockBuilder(ContainerInterface::class)
            ->getMock();
        $container->expects($this->never())
            ->method($this->anything());
        $firstListener = new CallableClass();
        $secondListener = function () {
        };
        $thirdListener = [
            new TestEventListener(),
            'preFoo',
        ];
        $listeners = [
            'test_event' => [
                0 => [
                    [
                        'callable' => $firstListener,
                    ],
                    [
                        'callable' => $secondListener,
                    ],
                    [
                        'callable' => $thirdListener,
                    ],
                ],
            ],
        ];
        $dispatcher = new ContainerAwareEventDispatcher($container, $listeners);
        $dispatcher->dispatch(new Event(), 'test_event');
        $this->assertTrue($thirdListener[0]->preFooInvoked);
    }
    public function testGetListenersWithServices() {
        $container = new ContainerBuilder();
        $container->register('listener_service', TestEventListener::class);
        $listeners = [
            'test_event' => [
                0 => [
                    [
                        'service' => [
                            'listener_service',
                            'preFoo',
                        ],
                    ],
                ],
            ],
        ];
        $dispatcher = new ContainerAwareEventDispatcher($container, $listeners);
        $actualListeners = $dispatcher->getListeners();
        $listenerService = $container->get('listener_service');
        $expectedListeners = [
            'test_event' => [
                [
                    $listenerService,
                    'preFoo',
                ],
            ],
        ];
        $this->assertSame($expectedListeners, $actualListeners);
    }
    
    /**
     * Tests argument order deprecation.
     *
     * @group legacy
     */
    public function testDispatchArgumentOrderDeprecation() {
        $this->expectDeprecation('Calling the Symfony\\Component\\EventDispatcher\\EventDispatcherInterface::dispatch() method with a string event name as the first argument is deprecated in drupal:9.1.0, an Event object will be required instead in drupal:10.0.0. See https://www.drupal.org/node/3154407');
        $container = new ContainerBuilder();
        $dispatcher = new ContainerAwareEventDispatcher($container, []);
        $dispatcher->dispatch('foo');
    }
    
    /**
     * Tests deprecation notice for Symfony Event class.
     *
     * @group legacy
     */
    public function testSymfonyEventDeprecation() {
        $this->expectDeprecation('Symfony\\Component\\EventDispatcher\\Event is deprecated in drupal:9.1.0 and will be replaced by Symfony\\Contracts\\EventDispatcher\\Event in drupal:10.0.0. A new Drupal\\Component\\EventDispatcher\\Event class is available to bridge the two versions of the class. See https://www.drupal.org/node/3159012');
        $container = new ContainerBuilder();
        $dispatcher = new ContainerAwareEventDispatcher($container, []);
        $dispatcher->dispatch(new SymfonyEvent());
    }
    
    /**
     * Tests dispatching Symfony events with core's event dispatcher.
     */
    public function testSymfonyEventDispatching() {
        $container = new ContainerBuilder();
        $dispatcher = new ContainerAwareEventDispatcher($container, []);
        $dispatcher->dispatch(new GenericEvent());
    }
    
    /**
     * Tests deprecation notice for Symfony Event class inheritance.
     *
     * @group legacy
     */
    public function testSymfonyInheritedEventDeprecation() {
        $this->expectDeprecation('Symfony\\Component\\EventDispatcher\\Event is deprecated in drupal:9.1.0 and will be replaced by Symfony\\Contracts\\EventDispatcher\\Event in drupal:10.0.0. A new Drupal\\Component\\EventDispatcher\\Event class is available to bridge the two versions of the class. See https://www.drupal.org/node/3159012');
        $container = new ContainerBuilder();
        $dispatcher = new ContainerAwareEventDispatcher($container, []);
        $dispatcher->dispatch(new SymfonyInheritedEvent());
    }
    public function testDispatchWithServices() {
        $container = new ContainerBuilder();
        $container->register('listener_service', TestEventListener::class);
        $listeners = [
            'test_event' => [
                0 => [
                    [
                        'service' => [
                            'listener_service',
                            'preFoo',
                        ],
                    ],
                ],
            ],
        ];
        $dispatcher = new ContainerAwareEventDispatcher($container, $listeners);
        $dispatcher->dispatch(new Event(), 'test_event');
        $listenerService = $container->get('listener_service');
        $this->assertTrue($listenerService->preFooInvoked);
    }
    public function testRemoveService() {
        $container = new ContainerBuilder();
        $container->register('listener_service', TestEventListener::class);
        $container->register('other_listener_service', TestEventListener::class);
        $listeners = [
            'test_event' => [
                0 => [
                    [
                        'service' => [
                            'listener_service',
                            'preFoo',
                        ],
                    ],
                    [
                        'service' => [
                            'other_listener_service',
                            'preFoo',
                        ],
                    ],
                ],
            ],
        ];
        $dispatcher = new ContainerAwareEventDispatcher($container, $listeners);
        $listenerService = $container->get('listener_service');
        $dispatcher->removeListener('test_event', [
            $listenerService,
            'preFoo',
        ]);
        // Ensure that other service was not initialized during removal of the
        // listener service.
        $this->assertFalse($container->initialized('other_listener_service'));
        $dispatcher->dispatch(new Event(), 'test_event');
        $this->assertFalse($listenerService->preFooInvoked);
        $otherService = $container->get('other_listener_service');
        $this->assertTrue($otherService->preFooInvoked);
    }
    public function testGetListenerPriorityWithServices() {
        $container = new ContainerBuilder();
        $container->register('listener_service', TestEventListener::class);
        $listeners = [
            'test_event' => [
                5 => [
                    [
                        'service' => [
                            'listener_service',
                            'preFoo',
                        ],
                    ],
                ],
            ],
        ];
        $dispatcher = new ContainerAwareEventDispatcher($container, $listeners);
        $listenerService = $container->get('listener_service');
        $actualPriority = $dispatcher->getListenerPriority('test_event', [
            $listenerService,
            'preFoo',
        ]);
        $this->assertSame(5, $actualPriority);
    }
    public function testInitialState() {
        $this->assertEquals([], $this->dispatcher
            ->getListeners());
        $this->assertFalse($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertFalse($this->dispatcher
            ->hasListeners(self::POSTFOO));
    }
    public function testAddListener() {
        $this->dispatcher
            ->addListener('pre.foo', [
            $this->listener,
            'preFoo',
        ]);
        $this->dispatcher
            ->addListener('post.foo', [
            $this->listener,
            'postFoo',
        ]);
        $this->assertTrue($this->dispatcher
            ->hasListeners());
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::POSTFOO));
        $this->assertCount(1, $this->dispatcher
            ->getListeners(self::PREFOO));
        $this->assertCount(1, $this->dispatcher
            ->getListeners(self::POSTFOO));
        $this->assertCount(2, $this->dispatcher
            ->getListeners());
    }
    public function testGetListenersSortsByPriority() {
        $listener1 = new TestEventListener();
        $listener2 = new TestEventListener();
        $listener3 = new TestEventListener();
        $listener1->name = '1';
        $listener2->name = '2';
        $listener3->name = '3';
        $this->dispatcher
            ->addListener('pre.foo', [
            $listener1,
            'preFoo',
        ], -10);
        $this->dispatcher
            ->addListener('pre.foo', [
            $listener2,
            'preFoo',
        ], 10);
        $this->dispatcher
            ->addListener('pre.foo', [
            $listener3,
            'preFoo',
        ]);
        $expected = [
            [
                $listener2,
                'preFoo',
            ],
            [
                $listener3,
                'preFoo',
            ],
            [
                $listener1,
                'preFoo',
            ],
        ];
        $this->assertSame($expected, $this->dispatcher
            ->getListeners('pre.foo'));
    }
    public function testGetAllListenersSortsByPriority() {
        $listener1 = new TestEventListener();
        $listener2 = new TestEventListener();
        $listener3 = new TestEventListener();
        $listener4 = new TestEventListener();
        $listener5 = new TestEventListener();
        $listener6 = new TestEventListener();
        $this->dispatcher
            ->addListener('pre.foo', $listener1, -10);
        $this->dispatcher
            ->addListener('pre.foo', $listener2);
        $this->dispatcher
            ->addListener('pre.foo', $listener3, 10);
        $this->dispatcher
            ->addListener('post.foo', $listener4, -10);
        $this->dispatcher
            ->addListener('post.foo', $listener5);
        $this->dispatcher
            ->addListener('post.foo', $listener6, 10);
        $expected = [
            'pre.foo' => [
                $listener3,
                $listener2,
                $listener1,
            ],
            'post.foo' => [
                $listener6,
                $listener5,
                $listener4,
            ],
        ];
        $this->assertSame($expected, $this->dispatcher
            ->getListeners());
    }
    public function testGetListenerPriority() {
        $listener1 = new TestEventListener();
        $listener2 = new TestEventListener();
        $this->dispatcher
            ->addListener('pre.foo', $listener1, -10);
        $this->dispatcher
            ->addListener('pre.foo', $listener2);
        $this->assertSame(-10, $this->dispatcher
            ->getListenerPriority('pre.foo', $listener1));
        $this->assertSame(0, $this->dispatcher
            ->getListenerPriority('pre.foo', $listener2));
        $this->assertNull($this->dispatcher
            ->getListenerPriority('pre.bar', $listener2));
        $this->assertNull($this->dispatcher
            ->getListenerPriority('pre.foo', function () {
        }));
    }
    public function testDispatch() {
        $this->dispatcher
            ->addListener('pre.foo', [
            $this->listener,
            'preFoo',
        ]);
        $this->dispatcher
            ->addListener('post.foo', [
            $this->listener,
            'postFoo',
        ]);
        $this->dispatcher
            ->dispatch(new Event(), self::PREFOO);
        $this->assertTrue($this->listener->preFooInvoked);
        $this->assertFalse($this->listener->postFooInvoked);
        $this->assertInstanceOf(Event::class, $this->dispatcher
            ->dispatch(new Event(), 'noevent'));
        $this->assertInstanceOf(Event::class, $this->dispatcher
            ->dispatch(new Event(), self::PREFOO));
        $event = new Event();
        $return = $this->dispatcher
            ->dispatch($event, self::PREFOO);
        $this->assertSame($event, $return);
    }
    public function testDispatchForClosure() {
        $invoked = 0;
        $listener = function () use (&$invoked) {
            ++$invoked;
        };
        $this->dispatcher
            ->addListener('pre.foo', $listener);
        $this->dispatcher
            ->addListener('post.foo', $listener);
        $this->dispatcher
            ->dispatch(new Event(), self::PREFOO);
        $this->assertEquals(1, $invoked);
    }
    public function testStopEventPropagation() {
        $otherListener = new TestEventListener();
        // postFoo() stops the propagation, so only one listener should
        // be executed
        // Manually set priority to enforce $this->listener to be called first
        $this->dispatcher
            ->addListener('post.foo', [
            $this->listener,
            'postFoo',
        ], 10);
        $this->dispatcher
            ->addListener('post.foo', [
            $otherListener,
            'postFoo',
        ]);
        $this->dispatcher
            ->dispatch(new Event(), self::POSTFOO);
        $this->assertTrue($this->listener->postFooInvoked);
        $this->assertFalse($otherListener->postFooInvoked);
    }
    public function testDispatchByPriority() {
        $invoked = [];
        $listener1 = function () use (&$invoked) {
            $invoked[] = '1';
        };
        $listener2 = function () use (&$invoked) {
            $invoked[] = '2';
        };
        $listener3 = function () use (&$invoked) {
            $invoked[] = '3';
        };
        $this->dispatcher
            ->addListener('pre.foo', $listener1, -10);
        $this->dispatcher
            ->addListener('pre.foo', $listener2);
        $this->dispatcher
            ->addListener('pre.foo', $listener3, 10);
        $this->dispatcher
            ->dispatch(new Event(), self::PREFOO);
        $this->assertEquals([
            '3',
            '2',
            '1',
        ], $invoked);
    }
    public function testRemoveListener() {
        $this->dispatcher
            ->addListener('pre.bar', $this->listener);
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREBAR));
        $this->dispatcher
            ->removeListener('pre.bar', $this->listener);
        $this->assertFalse($this->dispatcher
            ->hasListeners(self::PREBAR));
        $this->dispatcher
            ->removeListener('notExists', $this->listener);
    }
    public function testAddSubscriber() {
        $eventSubscriber = new TestEventSubscriber();
        $this->dispatcher
            ->addSubscriber($eventSubscriber);
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::POSTFOO));
    }
    public function testAddSubscriberWithPriorities() {
        $eventSubscriber = new TestEventSubscriber();
        $this->dispatcher
            ->addSubscriber($eventSubscriber);
        $eventSubscriber = new TestEventSubscriberWithPriorities();
        $this->dispatcher
            ->addSubscriber($eventSubscriber);
        $listeners = $this->dispatcher
            ->getListeners('pre.foo');
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertCount(2, $listeners);
        $this->assertInstanceOf(TestEventSubscriberWithPriorities::class, $listeners[0][0]);
    }
    public function testAddSubscriberWithMultipleListeners() {
        $eventSubscriber = new TestEventSubscriberWithMultipleListeners();
        $this->dispatcher
            ->addSubscriber($eventSubscriber);
        $listeners = $this->dispatcher
            ->getListeners('pre.foo');
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertCount(2, $listeners);
        $this->assertEquals('preFoo2', $listeners[0][1]);
    }
    public function testRemoveSubscriber() {
        $eventSubscriber = new TestEventSubscriber();
        $this->dispatcher
            ->addSubscriber($eventSubscriber);
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::POSTFOO));
        $this->dispatcher
            ->removeSubscriber($eventSubscriber);
        $this->assertFalse($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertFalse($this->dispatcher
            ->hasListeners(self::POSTFOO));
    }
    public function testRemoveSubscriberWithPriorities() {
        $eventSubscriber = new TestEventSubscriberWithPriorities();
        $this->dispatcher
            ->addSubscriber($eventSubscriber);
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->dispatcher
            ->removeSubscriber($eventSubscriber);
        $this->assertFalse($this->dispatcher
            ->hasListeners(self::PREFOO));
    }
    public function testRemoveSubscriberWithMultipleListeners() {
        $eventSubscriber = new TestEventSubscriberWithMultipleListeners();
        $this->dispatcher
            ->addSubscriber($eventSubscriber);
        $this->assertTrue($this->dispatcher
            ->hasListeners(self::PREFOO));
        $this->assertCount(2, $this->dispatcher
            ->getListeners(self::PREFOO));
        $this->dispatcher
            ->removeSubscriber($eventSubscriber);
        $this->assertFalse($this->dispatcher
            ->hasListeners(self::PREFOO));
    }
    public function testEventReceivesTheDispatcherInstanceAsArgument() {
        $listener = new TestWithDispatcher();
        $this->dispatcher
            ->addListener('test', [
            $listener,
            'foo',
        ]);
        $this->assertNull($listener->name);
        $this->assertNull($listener->dispatcher);
        $this->dispatcher
            ->dispatch(new Event(), 'test');
        $this->assertEquals('test', $listener->name);
        $this->assertSame($this->dispatcher, $listener->dispatcher);
    }
    
    /**
     * @see https://bugs.php.net/bug.php?id=62976
     *
     * This bug affects:
     *  - The PHP 5.3 branch for versions < 5.3.18
     *  - The PHP 5.4 branch for versions < 5.4.8
     *  - The PHP 5.5 branch is not affected
     */
    public function testWorkaroundForPhpBug62976() {
        $dispatcher = $this->createEventDispatcher();
        $dispatcher->addListener('bug.62976', new CallableClass());
        $dispatcher->removeListener('bug.62976', function () {
        });
        $this->assertTrue($dispatcher->hasListeners('bug.62976'));
    }
    public function testHasListenersWhenAddedCallbackListenerIsRemoved() {
        $listener = function () {
        };
        $this->dispatcher
            ->addListener('foo', $listener);
        $this->dispatcher
            ->removeListener('foo', $listener);
        $this->assertFalse($this->dispatcher
            ->hasListeners());
    }
    public function testGetListenersWhenAddedCallbackListenerIsRemoved() {
        $listener = function () {
        };
        $this->dispatcher
            ->addListener('foo', $listener);
        $this->dispatcher
            ->removeListener('foo', $listener);
        $this->assertSame([], $this->dispatcher
            ->getListeners());
    }
    public function testHasListenersWithoutEventsReturnsFalseAfterHasListenersWithEventHasBeenCalled() {
        $this->assertFalse($this->dispatcher
            ->hasListeners('foo'));
        $this->assertFalse($this->dispatcher
            ->hasListeners());
    }
    public function testHasListenersIsLazy() {
        $called = 0;
        $listener = [
            function () use (&$called) {
                ++$called;
            },
            'onFoo',
        ];
        $this->dispatcher
            ->addListener('foo', $listener);
        $this->assertTrue($this->dispatcher
            ->hasListeners());
        $this->assertTrue($this->dispatcher
            ->hasListeners('foo'));
        $this->assertSame(0, $called);
    }
    public function testDispatchLazyListener() {
        $called = 0;
        $factory = function () use (&$called) {
            ++$called;
            return new TestWithDispatcher();
        };
        $this->dispatcher
            ->addListener('foo', [
            $factory,
            'foo',
        ]);
        $this->assertSame(0, $called);
        $this->dispatcher
            ->dispatch(new Event(), 'foo');
        $this->dispatcher
            ->dispatch(new Event(), 'foo');
        $this->assertSame(1, $called);
    }
    public function testRemoveFindsLazyListeners() {
        $test = new TestWithDispatcher();
        $factory = function () use ($test) {
            return $test;
        };
        $this->dispatcher
            ->addListener('foo', [
            $factory,
            'foo',
        ]);
        $this->assertTrue($this->dispatcher
            ->hasListeners('foo'));
        $this->dispatcher
            ->removeListener('foo', [
            $test,
            'foo',
        ]);
        $this->assertFalse($this->dispatcher
            ->hasListeners('foo'));
        $this->dispatcher
            ->addListener('foo', [
            $test,
            'foo',
        ]);
        $this->assertTrue($this->dispatcher
            ->hasListeners('foo'));
        $this->dispatcher
            ->removeListener('foo', [
            $factory,
            'foo',
        ]);
        $this->assertFalse($this->dispatcher
            ->hasListeners('foo'));
    }
    public function testPriorityFindsLazyListeners() {
        $test = new TestWithDispatcher();
        $factory = function () use ($test) {
            return $test;
        };
        $this->dispatcher
            ->addListener('foo', [
            $factory,
            'foo',
        ], 3);
        $this->assertSame(3, $this->dispatcher
            ->getListenerPriority('foo', [
            $test,
            'foo',
        ]));
        $this->dispatcher
            ->removeListener('foo', [
            $factory,
            'foo',
        ]);
        $this->dispatcher
            ->addListener('foo', [
            $test,
            'foo',
        ], 5);
        $this->assertSame(5, $this->dispatcher
            ->getListenerPriority('foo', [
            $factory,
            'foo',
        ]));
    }
    public function testGetLazyListeners() {
        $test = new TestWithDispatcher();
        $factory = function () use ($test) {
            return $test;
        };
        $this->dispatcher
            ->addListener('foo', [
            $factory,
            'foo',
        ], 3);
        $this->assertSame([
            [
                $test,
                'foo',
            ],
        ], $this->dispatcher
            ->getListeners('foo'));
        $this->dispatcher
            ->removeListener('foo', [
            $test,
            'foo',
        ]);
        $this->dispatcher
            ->addListener('bar', [
            $factory,
            'foo',
        ], 3);
        $this->assertSame([
            'bar' => [
                [
                    $test,
                    'foo',
                ],
            ],
        ], $this->dispatcher
            ->getListeners());
    }

}
class CallableClass {
    public function __invoke() {
    }

}
class TestEventListener {
    public $preFooInvoked = FALSE;
    public $postFooInvoked = FALSE;
    
    /**
     * Listener methods.
     */
    public function preFoo(Event $e) {
        $this->preFooInvoked = TRUE;
    }
    public function postFoo(Event $e) {
        $this->postFooInvoked = TRUE;
        $e->stopPropagation();
    }

}
class TestWithDispatcher {
    public $name;
    public $dispatcher;
    public function foo(Event $e, $name, $dispatcher) {
        $this->name = $name;
        $this->dispatcher = $dispatcher;
    }

}
class TestEventSubscriber implements EventSubscriberInterface {
    public static function getSubscribedEvents() {
        return [
            'pre.foo' => 'preFoo',
            'post.foo' => 'postFoo',
        ];
    }

}
class TestEventSubscriberWithPriorities implements EventSubscriberInterface {
    public static function getSubscribedEvents() {
        return [
            'pre.foo' => [
                'preFoo',
                10,
            ],
            'post.foo' => [
                'postFoo',
            ],
        ];
    }

}
class TestEventSubscriberWithMultipleListeners implements EventSubscriberInterface {
    public static function getSubscribedEvents() {
        return [
            'pre.foo' => [
                [
                    'preFoo1',
                ],
                [
                    'preFoo2',
                    10,
                ],
            ],
        ];
    }

}
class SymfonyInheritedEvent extends SymfonyEvent {

}