Single letter classnames wrongly cause C0103 (invalid-name)

[Starwort]

Steps to reproduce

1. from typing import TypeVar
2. T = TypeVar('T')
3. C0103: Class name "T" doesn't conform to PascalCase naming style (invalid-name)

Current behaviour

C0103: Class name "T" doesn't conform to PascalCase naming style (invalid-name)

Expected behaviour

no C0103

pylint --version output

pylint 2.4.3
astroid 2.3.1
Python 3.8.0 (default, Oct 15 2019, 14:05:58)
[GCC 7.4.0]

[PCManticore]

This is a duplicate of #2018. The issue is that the naming styles need at least 3 characters by default so T fails the check since it is too short. You can check that yourself by passing --include-naming-hint=y which will show the regular expression against which the name is validated.

[phiresky]

It would be good if there was a way to make pylint recognize this correctly as a type variable instead of a "class name", since the usual convention for type variables is to be single-letter (as opposed to class names).

I don't want to disable the lint for real class names, but I do want to disable it for type vars.

[DanielNoord]

We're working on this in #5221. It (hopefully) will be part of the next version!

[phiresky]

Great! I guess this issue is really a dupe of #3401 then instead of #2018 (referencing since I found only this one via google)

[DanielNoord]

You're right! Thanks for pointing that out 😄