[Psalm] ProviderInterface does not allow for arrays to be returned

[nesl247]

API Platform version(s) affected: 3.0.7

Description
In

core/src/State/ProviderInterface.php

Line 23 in 3a845f1

* @template T of object

the type is defined to be an object. Because of this, when running psalm, it complains if a provider returns an array, given that an array is not an object.

ERROR: InvalidTemplateParam - src/TestProvider.php:13:31 - Extended template param T expects type object, type array<array-key, mixed> given (see https://psalm.dev/183)
class TestProvider implements ProviderInterface

How to reproduce

<?php

declare(strict_types=1);

namespace App;

use ApiPlatform\Metadata\Operation;
use ApiPlatform\State\ProviderInterface;

/**
 * @implements ProviderInterface<array>
 */
class TestProvider implements ProviderInterface
{
    public function provide(Operation $operation, array $uriVariables = [], array $context = []): object|array|null
    {
        return [];
    }
}

Possible Solution
Change it to T of object|array. I'm not sure if this is incorrect, but I think it's valid, and it does fix the issue.

Additional Context

[soyuka]

@tyx can I have your insight on this?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[soyuka]

related #5443

[nesl247]

@soyuka this is still an issue in v3.3.12 using phpstan.