unused-import false positive for names in string argument to typing.cast

[lggruspe]

Bug description

example.py:

# pylint: disable=missing-docstring
from pathlib import Path
import typing as t

paths = t.cast("set[Path]", set())

Configuration

No response

Command used

pylint example.py

Pylint output

************* Module example
example.py:2:0: W0611: Unused Path imported from pathlib (unused-import)

------------------------------------------------------------------
Your code has been rated at 6.67/10 (previous run: 6.67/10, +0.00)

Expected behavior

There shouldn't be any messages.

Pylint version

pylint 2.15.3
astroid 2.12.10
Python 3.10.7 (main, Sep  7 2022, 00:00:00) [GCC 12.2.1 20220819 (Red Hat 12.2.1-1)]

OS / Environment

fedora 36

Additional dependencies

No response

[clavedeluna]

I'm able to reproduce. Worth noting, though, that even PyCharm registers Path as unused

[bersbersbers]

This false positive is prone to receiving much additional exposure now that ruff has implemented TC006, compare astral-sh/ruff#14511, leading to the stringification of the type argument in practically all cast calls.

TC006 is still in preview mode, but that won't have to remain that way. https://docs.astral.sh/ruff/rules/runtime-cast-value/

[Pierre-Sassoulas]

Nice catch @bersbersbers thank you. This check has to be activated in ruff so it's not going to be a flash flood, but I labelled as "need PR".