Fix #96 none handling for select and extend-select

[wyuenho]

I'm not exactly sure if this is the best way to fix this issue, but this seems to be the only way to fix without haven't to rewrite a whole lot of tests.

[codecov]

Codecov Report

Merging #98 (3e454d2) into main (7a5f727) will increase coverage by 0.0%.
The diff coverage is 100.0%.

@@          Coverage Diff          @@
##            main     #98   +/-   ##
=====================================
  Coverage   96.9%   96.9%           
=====================================
  Files          3       3           
  Lines        420     421    +1     
=====================================
+ Hits         407     408    +1     
  Misses        13      13           

Impacted Files	Coverage Δ
flake8_type_checking/plugin.py	85.0% <100.0%> (+0.3%)	⬆️

[sondrelg]

Thanks for opening the issue and PR @wyuenho! Just so I can understand the issue properly, do you have a way for me to replicate the issue locally when on the flake8 main branch?

[wyuenho]

do you have a way for me to replicate the issue locally

Just install flake8 HEAD and flake8-type-checking in any project, write a .flake8 config without a select value, which is allowed, and that's it.

[sondrelg]

Running

deactivate \
  && rm -rf venv \
  && python3 -m venv venv --upgrade-deps \
  && source venv/bin/activate \
  && pip install git+https://github.com/pycqa/flake8@main flake8-type-checking \
  && echo "[flake8]\nexclude = .venv" > .flake8 \
  && echo "print('test')" > main.py \
  && flake8 .

I'm not able to replicate on Python 3.9. What's missing?

[wyuenho]

Ah ok, so for some reason this code path only gets hit when the file contains something like this:

from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from collections.abc import AsyncGenerator

I'm not entirely sure why...

[sondrelg]

Even with the example above I was not able to reproduce the issue yesterday. Would you be able to provide step-by-step instructions for how to replicate?

I'll get home from holidays tomorrow, and will have a bit more time available then. If you're able to provide replicating steps, I'll review and merge by Thursday most likely 👍 Thanks again for opening the PR!

[sondrelg]

After reviewing the PR, this seems sensible regardless of whether I'm able to replicate or not 🙂 Thanks!

[wyuenho]

I can reproduce this pretty consistently on both 3.9 and 3.10. I would check your pip caches and hardcode a commit hash into the package version instead of a tag and try again.

Thanks for merging! I guess now what's left is actually updating the readme to reflect the recommended way to config the rules for flake8 >= 4, which is extend-select.