How to support dynamic typehints via Generics?

[niconoe-]

Hi everyone!

I'm working with a mocking library that allows me to create mock objects from one or several class/interface names. My problem is that this library can't give me the good return type of the object I'm mocking and I don't know how to define the return type of the builder method, even with generics.

Let's give this simplified example: https://phpstan.org/r/5d9c49ec-1d1c-4862-8091-5a14ac7bd4fc

In this snippet, I expect:

• $a to be inferred of type MockInterface&A ;
• $bcd to be inferred of type MockInterface&B&C&D ;
• $build to be inferred of type MockInterface&Build ;

How can I acheive this by correctly defining the template or the @return definition of my mocker?

Thanks a lot.

[ondrejmirtes]

This works as expected I believe: https://phpstan.org/r/f06ef7e7-6d54-4734-b45e-a05bd50adc09

@template Tabove a class doesn't make sense for static methods.

[niconoe-]

Lovely! Thank you very much!

EDIT: as @stof said, this is actually not OK for list of interfaces. This proposal fits my urgent needs, but due to the fact it returns a union rather an intersection, it will not be OK in the future 😢

[stof]

this does not work well for a list of interfaces, as it returns a union of those rather than an intersection

[smaddock]

I am running into this as well #13143