[BUG] Circular dependency issue when using EntityMananger in constructor of subscribers

[vv12131415]

Package version, Laravel version Package version - latest (1.5.4) Laravel - latest (6.x)

Expected behaviour

I can resolve depdendency as ctor injection

<?php

declare(strict_types=1);

namespace Foo;

use Doctrine\Common\EventSubscriber;
use Doctrine\ORM\EntityManagerInterface;

class Bar implements EventSubscriber
{
    /** @var EntityManagerInterface */
    private $em;
    
    public function __construct(EntityManagerInterface $em)
    {
        $this->em = $em;
    }
}

Actual behaviour

<?php

declare(strict_types=1);

namespace Foo;

use Doctrine\Common\EventSubscriber;
use Doctrine\ORM\EntityManagerInterface;

class Bar implements EventSubscriber
{
    /** @var EntityManagerInterface|null */
    private $em;
    
    public function getEntityManager()
    {
        if (!isset(this->em)) {
            $this->em = app(EntityManagerInterface::class); // with service locator, but it's wrong
        }
        
        return $this->em;
    }
}

Steps to reproduce the behaviour

just inject EntityManager/SomeRepository into EventSubscriber

[eigan]

This is not so easy to fix. Which EntityManager should be sent to the repository/constructor? I guess the one which is being created, but not so sure how we can provide that when the constructor is requesting a repository.

Relevant code is EntityManagerFactory::registerSubscribers.

We could to:

$resolvedSubscriber = $this->container->make($subscriber, [
    'entityManager' => $manager,
    'em' => $manager
]);

But this will not solve the issue with repositories.

---

Your subscribe-methods will receive an EventArgs object which should provide the EntityManager though. Isnt this sufficient?

public function onFlush(OnFlushEventArgs $args): void 
{
   $entityManager = $args->getEntityManager();
   $repo = $entityManager->getRepository(MyEntity::class);
 }

[vv12131415]

Yes we can use your last example. We can also do something like this

https://github.com/EnMarche/en-marche.fr/blob/2d43a966357ff2bddbca36ae9599025ff95862dc/src/EventListener/ManageReferentTeamMembersListener.php#L39

but best result for me is ctor injection, like here

https://github.com/EnMarche/en-marche.fr/blob/33111a0151098cfde26bb676b4432774b1a3e0df/src/EventSubscriber/ChangeIdeaAuthorCategoryListener.php#L11

the last one is available since lazy services in symfony

https://github.com/EnMarche/en-marche.fr/blob/8e0a12e8f774278fcf82033edebae6e87d4d17e8/app/config/services/services.xml#L182-L185

---

I know that I'm showing examples from symfony project. I'm trying to push lazy services to Laravel (https://github.com/laravel/ideas/issues/1436), but don't have results