TypeGuess::getBestGuess expects array<array-key, TypeGuess&static>, parent type array{TypeGuess} provided

[VincentLanglet]

I simplified the use of this method: https://github.com/symfony/form/blob/5.3/Guess/Guess.php#L67

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

I'm getting

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

I don't understand the error, the static phpdoc is unclear to me.

Is my example wrong or should the symfony phpdoc be updated ?

[weirdan]

Looks like a bug to me. The issue emitted there is basically preventing you from doing this (unsafe as $a and $b do not necessarily receive objects of the same class): https://psalm.dev/r/9e18c10edc

<?php

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

class A extends Guess {}
class B extends Guess {}

class FooFoo {
    public function guess(Guess $a, Guess $b): ?Guess {
        return $a->getBestGuess([$b]);
    }
}

However in your case we know exactly what class static refers to (as it's a static call), and it's given an instance of the same type (or subtype, but that's ok).

[VincentLanglet]

Looks like a bug to me.

Then an issue seems more appropriate #5938

Thanks