Recognize ``__init__.pyi`` to lint stub files

[jolaf]

I'm creating *.pyi stubs for large libraries and I'd like to use pylint (as well as mypy) to make sure the stubs are clean.

The files I'm trying to lint are located in a directory hierarchy having __init__.pyi file in each subdirectory. Unfortunately, pylint only detects __init__.py as a "submodule root" and treats __init__.pyi as a regular file, not a submodule root, so it can't properly recognized objects defined in them.

I would suggest the following behaviour:

• If import of an object from a module is located in a .py file, the source code for that object should be looked up in a corresponding __init__.py file, as it is now.

• If import of an object from a module is located in a .pyi file, the source code for that object should be looked up in a corresponding __init__.pyi file, not __init__.py file, as it is does now.

[PCManticore]

This probably makes sense. It would require some re-engineering of the import system though so might not be trivial to accomplish.

[clavedeluna]

Is this issue a duplicate of #4987 , vice versa?

[Pierre-Sassoulas]

Closing as duplicate of #4987 which is more detailed and pinned, thank you @clavedeluna .