Add generics to ArgumentMetadata::getAttributes

[Seldaek]

Q	A
Branch?	5.3
Bug fix?	yes
New feature?	no
Deprecations?	no
Tickets	Fix #...
License	MIT
Doc PR	symfony/symfony-docs#...

This is a bit of an unfortunate situation because the function does too many things. If stronger typing was applied earlier on, it would have been evident that typing this correctly is pretty much impossible, and that would have helped guide the design to use a separate function to retrieve all attributes and some attributes.

e.g. the ideal outcome would be for getAttributes(Foo::class) to be typed as such:

    /**
     * @template T
     * @param class-string<T> $name
     * @return array<T>
     */

So that the result is guaranteed to be an array of Foo objects.

The fact that $name is nullable throws all this off though.. So I guess the only good way forward would be to deprecate null, or deprecate passing $name and add a getAttributesByClassName(string $class, int $flags = 0) ?

I'm not sure if merging this as is is valuable or not, or if you'd rather get the deprecation and new method targetting 6.1?

[derrabus]

Do you need this as a bugfix? We usually merge this kind of change to the feature branch.

[nicolas-grekas]

That reminds me #40783, we should not forget about it 👼

[Seldaek]

Well, do I need it? No, I worked around it already with an instanceof check to calm PHPStan down..

I just assumed this was going to be a simple tweak that could be done as bugfix, but then I noticed the API is kinda bad and thus the types are too broad and yeah.. the usual rabbit hole :)

[derrabus]

Okay, let's target 6.1 then. You never know who's parsing those docblocks these days. 🙈

[Seldaek]

I'm fine rebasing this for 6.1, but the question remains what the better API is.. do others care about fixing the API and deprecating things one way or the other? Or is it just me? :)

[ro0NL]

try https://psalm.dev/r/eb6309306d

[stof]

This syntax for conditional types works in psalm, but is not supported in phpstan or in PHPStorm (without the psalm plugin) or other IDEs. So this makes it unacceptable to be used in the Symfony phpdoc.

[ro0NL]

phpstan/phpstan#3853 we wait

personally, psalm is like a god to me ;);)

[nicolas-grekas]

(rebase needed)

[Seldaek]

Ok rebased. Added a second method to have cleaner return types. I guess one could add a deprecation warning if you pass $name to getAttributes() but I'm not sure if it's worth bothering people with this.

[fabpot]

Thank you @Seldaek.