Support for ServiceLocator

[andrey-bondar]

Now when private services are fetching from Psr\Container\ContainerInterface::get(), an error "Service "%s" is private" occurred.

But Symfony has ServiceLocators in order to define smaller containers with public access to services.

This PR solves error "Service "%s" is private" when service is fetching from ServiceLocator.

[ondrejmirtes]

Hi, what errors it resolves? Please attach a test too.

[andrey-bondar]

@ondrejmirtes I've attached tests

[ondrejmirtes]

Thank you!

[Wirone]

Sorry for digging the old issue @ondrejmirtes but I'm implementing Symfony extension in our app and I got "Service ... is private" errors. I've found out that our app uses service locators BUT they are not extending Symfony\Component\DependencyInjection\ServiceLocator but only implementing Psr\Container\ContainerInterface. I can't extend Symfony's ServiceLocator because we already have custom implementation of get(), so all I could do is implementing Symfony\Contracts\Service\ServiceProviderInterface (which is also implemented in ServiceLocator). Unfortunately it won't be resolved properly in PHPStan\Rules\Symfony\ContainerInterfacePrivateServiceRule::processNode() since it checks explicitly for ServiceLocator.

What do you think, is it possible to change condition ($isServiceLocator → $isServiceProvider) so raw ServiceProviderInterface would be supported instead of concrete ServiceLocator?

[ondrejmirtes]

Feel free to send a PR with a test and a fix and we'll see (mostly what @lookyman will say about it :))