[4.25.0] InvalidArgument for result of a method with a static return type

[vudaltsov]

<?php

declare(strict_types=1);

namespace HappyInc;

abstract class A
{
}

final class B extends A
{
    public static function create(): static
    {
        return new self();
    }
}

final class Service
{
    public function do(): void
    {
        $this->acceptA(B::create());
    }

    private function acceptA(A $_a): void
    {
    }
}

gives

ERROR: InvalidArgument - src/A.php:23:24 - Argument 1 of HappyInc\Service::acceptA expects HappyInc\A, HappyInc\Service provided (see https://psalm.dev/004)
        $this->acceptA(B::create());

in 4.25.0.

By the way, for some reason https://psalm.dev/r/6081a71dec says "No issues!".

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/6081a71dec

<?php

declare(strict_types=1);

namespace HappyInc;

abstract class A
{
}

final class B extends A
{
    public static function create(): static
    {
        return new self();
    }
}

final class Service
{
    public function do(): void
    {
        $this->acceptA(B::create());
    }

    private function acceptA(A $_a): void
    {
    }
}

Psalm output (using commit 7c4228f):

No issues!

[vudaltsov]

Oh, I see, psalm.dev is at 7c4228f, not d7cd84c.

[orklah]

Hey @someniatko , it could be a result of #8249. Would you mind taking a look?

[VincentLanglet]

I have the same issue with the following code https://psalm.dev/r/3765f8a43d

If you need a reproducer, you can try
https://github.com/sonata-project/SonataAdminBundle/blob/4.x/src/FieldDescription/TypeGuesserChain.php#L57
Which has two more issue since 4.25

ERROR: MoreSpecificReturnType - src/FieldDescription/TypeGuesserChain.php:57:73 - The declared return type 'Symfony\Component\Form\Guess\TypeGuess|null' for Sonata\AdminBundle\FieldDescription\TypeGuesserChain::guess is more specific than the inferred return type 'Symfony\Component\Form\Guess\Guess&static|null' (see https://psalm.dev/070)
    public function guess(FieldDescriptionInterface $fieldDescription): ?TypeGuess


ERROR: LessSpecificReturnStatement - src/FieldDescription/TypeGuesserChain.php:69:16 - The type 'Symfony\Component\Form\Guess\Guess&static|null' is more general than the declared return type 'Symfony\Component\Form\Guess\TypeGuess|null' for Sonata\AdminBundle\FieldDescription\TypeGuesserChain::guess (see https://psalm.dev/129)
        return TypeGuess::getBestGuess($guesses);

If it require a rework of static, might be worth taking a look at #5938 too.

[psalm-github-bot]

I found these snippets:

https://psalm.dev/r/3765f8a43d

<?php

abstract class Guess 
{
    /**
     * @param static[] $guesses An array of guesses
     *
     * @return static|null
     */
    public static function getBestGuess(array $guesses)
    {
        return $guesses[0] ?? null;
    }
}

class TypeGuess extends Guess
{
}

class FooFoo
{
    public function guess(TypeGuess $object): ?TypeGuess
    {
       
        return TypeGuess::getBestGuess([$object]);
    }
}

Psalm output (using commit 7c4228f):

ERROR: ArgumentTypeCoercion - 25:40 - Argument 1 of TypeGuess::getBestGuess expects array<array-key, TypeGuess&static>, parent type array{TypeGuess} provided

[someniatko]

@orklah I will take a look tomorrow. My suspect is hasStaticInType() returned false for some reason, but that's really strange, there should be enough tests already written, one of which should have caught this.

[AndrolGenhald]

@vudaltsov does it still happen if you return new static() instead of new self()? Maybe that's the culprit?

[vudaltsov]

@AndrolGenhald, no, it gives the same error. Anyway, in a final class it's valid to return new self in a : static method.