Service subscriber does not support custom service names

[annuh]

Possibly related issue(s): #101

It seems the Psalm Symfony plugin doesn't support service subscribers using a custom service name.

Here is the related documentation: https://symfony.com/doc/current/service_container/service_subscribers_locators.html#including-services

For example the following PHP code

<?php

use Psr\Container\ContainerInterface;
use Symfony\Contracts\Service\ServiceSubscriberInterface;

class ServiceProvider implements ServiceSubscriberInterface
{
    public function __construct(private ContainerInterface $container) {}

    public function getFooService(): FooService
    {
        return $this->container->get('foo');
    }

    public static function getSubscribedServices(): array
    {
        return [
            'foo' => FooService::class,
        ];
    }
}

results in the following error:

ERROR: ServiceNotFound - src/Service/ServiceProvider.php- Service "foo" not found
        return $this->container->get('foo');

Is this a missing feature or am I doing something wrong? 🙂

[seferov]

@annuh thank you for the report.

According to related tests defined here https://github.com/psalm/psalm-plugin-symfony/blob/master/tests/acceptance/acceptance/ServiceSubscriber.feature the feature is working as expected. Could you please provide a test case that fails with your scenario?

[annuh]

It turns this issue is caused by using const service names.

Here is a test case to reproduce our scenario:

  Scenario: Asserting psalm recognizes return type of services defined in getSubscribedServices
    Given I have the following code
      """
      <?php

      use Doctrine\ORM\EntityManagerInterface;
      use Psr\Container\ContainerInterface;
      use Symfony\Contracts\Service\ServiceSubscriberInterface;
      use Symfony\Component\Validator\Validator\ValidatorInterface;

      class SomeController implements ServiceSubscriberInterface
      {
        private const EM_SERVICE_NAME = 'em2';
        private $container;

        public function __construct(ContainerInterface $container)
        {
          $this->container = $container;
        }

        public function __invoke()
        {
          /** @psalm-trace $entityManager */
          $entityManager = $this->container->get('em');

          /** @psalm-trace $entityManager2 */
          $entityManager2 = $this->container->get(self::EM_SERVICE_NAME);

          /** @psalm-trace $validator */
          $validator = $this->container->get(ValidatorInterface::class);
        }

        public static function getSubscribedServices()
        {
          return [
            'em' => EntityManagerInterface::class, // with key
            self::EM_SERVICE_NAME => EntityManagerInterface::class, // with constant
            ValidatorInterface::class, // without key
          ];
        }
      }
      """
    When I run Psalm
    Then I see these errors
      | Type  | Message                                                              |
      | Trace | $entityManager: Doctrine\ORM\EntityManagerInterface                  |
      | Trace | $validator: Symfony\Component\Validator\Validator\ValidatorInterface |
    And I see no other errors

This results now in this error:

1) Service Subscriber: Asserting psalm recognizes return type of services defined in getSubscribedServices
 Test  tests/acceptance/acceptance/ServiceSubscriber.feature:Asserting psalm recognizes return type of services defined in getSubscribedServices
There were errors: 
| MixedAssignment | Unable to determine the type that $entityManager2 is being assigned to |
| Trace           | $entityManager2: mixed                                                 |
| ServiceNotFound | Service "self" not found                                               |

Is Psalm even capable of understanding const in this case?