PHPStan complains about return type of instantiateWith in a PersistentProxyObjectFactory factory

[marien-probesys]

Hi,

I use PHPStan to verify the typing in my application. I have an issue when using the instantiateWith() method in a PersistentProxyObjectFactory factory.

instantiateWith() is declared in the ObjectFactory and must return an object of the template class T. However, when inheriting from the PersistentProxyObjectFactory class, T becomes T&Proxy<T>. Meaning that PHPStan expects instantiateWith() to return a T&Proxy<T> object.

namespace App\Tests\Factory;

use App\Entity\MyEntity;
use Zenstruck\Foundry\Persistence\PersistentProxyObjectFactory;

/**
 * @extends PersistentProxyObjectFactory<MyEntity>
 */
final class MyEntityFactory extends PersistentProxyObjectFactory
{
    protected function initialize(): static
    {
        // The return type of instantiateWith is correct, but PHPStan expects a MyEntity&Proxy<MyEntity> and fail.
        return $this->instantiateWith(function (array $attributes, string $class): MyEntity {
            $myEntity = new MyEntity();

            // …

            return $myEntity;
        });
    }

    // …
}

[nikophil]

Hi @marien-probesys

which Foundry's (and PHPStan) version are you using?
I've recently added specific phpdoc for this case

[marien-probesys]

Hi @nikophil, thanks for your answer. I'm using PHPStan 1.12.11 (the latest version of v1) and Foundry 2.2.2.

I'm sorry I made a mistake in my explanations: the problem is not with the instantiateWith() method directly, but with its callable parameter $instantiator. It is its return type which is wrong! (so the InstantiatorCallable type defined at the top of the file)

If you need it, I can create a minimal project tomorrow in order to reproduce the problem.

[marien-probesys]

I've created a repository to reproduce the problem: https://github.com/marien-probesys/foundry-721

You can see the error here: https://github.com/marien-probesys/foundry-721/actions/runs/11915667680/job/33206464561

And the factory: https://github.com/marien-probesys/foundry-721/blob/main/src/Factory/PostFactory.php

[nikophil]

thanks for your reproducer! I'll soon check this

[nikophil]

Hi, I really don't know what to do to make PHPStan happy here 🤔

you code seems OK, but the phpdoc for ObjectFactory::instantiateWith() seems also OK 🤔

@kbond any thoughts?

[kbond]

That's a bummer. Feels like it's because the string in the closure isn't being considered class-string<Post>?

[nikophil]

nope, it is because of the proxy: if the factory extends from PersistentObjectFactory instead of PersistentProxyObjectFactory, phpstan is happy