ClassMetadata template should not be template-covariant since PHP 8.4

[VincentLanglet]

Bug Report

Q	A
Version	all since 2.1

Summary

In php 8.4+ ReflectionClass lost his template-covariant annotation because of proxy methods,
see phpstan/phpstan-src@25ec5eb

This means that an interface which has a method returning ReflectionClass<T> cannot be use a covariant template too.

Expected behavior

I assume doctrine should

• Change template-covariant into template for

  persistence/src/Mapping/ClassMetadata.php

  Line 12 in 00bd9cc

  * @template-covariant T of object

• Change the same for classes implementings the ClassMetadata interface (in ORM and ODM)

Related issue on phpstan-doctrine
phpstan/phpstan-doctrine#646
and PR phpstan/phpstan-doctrine#663
(Maybe ondrej will have a better answer/solution ?)

How to reproduce

I assume the error will happen on the doctrine codebase as soon as you will target a PHP version higher or equal to 8.4,
but currently you're on 8.1 for phpstan

persistence/phpstan.neon

Line 9 in 00bd9cc

phpVersion: 80100

[greg0ire]

@VincentLanglet please take a look at #473

[VincentLanglet]

@VincentLanglet please take a look at #473

Nice, it works well indeed
https://phpstan.org/r/58e7edd2-0c13-488c-b0df-faeef3f4671d

WDYT about using @return ReflectionClass<covariant T> on 4.x too (or even 3.x ?) ?

[greg0ire]

I think it might qualify as a static analysis fix indeed, so backporting it on 3.x would be fine 🤔