Covariant generic return types

[spawnia]

Hi, thanks for this great project.

I am trying to provide proper types in one of my projects (webonyx/graphql-php#991), but have an issue with correctly typing a method that clones a value:

I have boiled this down to a minimal example here: https://phpstan.org/r/f64c26bf-9543-4f57-9024-a415d78b2cd2

After digging around the issues, I found that @template-covariant might be what I need, but it does not work in functions: https://phpstan.org/r/6efcad0e-33ad-4934-a167-f8e0ea3b2c79

Putting it into the classes PHPDoc also does not lead to the desired result: https://phpstan.org/r/5b889879-f8ce-4ea0-874a-264effe57895

How can this be done? Can it be done at all?

@simPod @LastDragon-ru

[ondrejmirtes]

This is a bug, please open an issue.

[spawnia]

#5844, thank you for your swift response