false positive for new union types

[bo5o]

Bug report

What's wrong

PEP604 allows | to be used for union types. you can now write str | int instead of Union[str, int] or str | None instead of Optional[str] and even isinstance(foo, str | int) will work. This feature is accepted for Python 3.10, but you can use it already with mypy>=0.800 and from __future__ import annotations (which will become the default in Python 3.10 as well).

However, currently this syntax triggers WPS465.

A workaround is to write type declarations as strings like "str | None" or "str | int".

How it should be

The | operator will be used a lot in future Python versions (e.g. Structural Pattern Matching uses it to define or-patterns). So I think this rule should not cause a violation for these special cases.

System information

OS: Ubuntu 18.04.5 LTS x86_64
Python: 3.7.9
pip: 21.0.1

flake8 information

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[sobolevn]

Oh wow! Thanks for the report! I was not aware that this is already possible. 👍

[sobolevn]

Btw, PRs are welcome!