Swap in tomllib/tomli for toml.

[sacsar]

Description

Fixes #339 -- the toml package does not support heterogenous arrays, which are now allowed in the toml spec. This commit swaps in tomllib from the standard library for Python >= 3.11 and its backport tomli for older versions.

Checklist:

• [X] I have updated the documentation in the README.md file or my changes don't require an update.
• [x] I have added an entry in CHANGELOG.md.
• [X] I have added or adapted tests to cover my changes.
• [X] I have run tox -e fix-style to format my code and checked the result with tox -e style.

[sacsar]

Note: While the tox style check passes, flake8 finds errors when run via pre-commit (including in vulture/core.py, which I didn't touch). I believe this is flake8 and black fighting, but I didn't go too far down the rabbit hole and ended up using --no-verify.

[sacsar]

Note: While the tox style check passes, flake8 finds errors when run via pre-commit (including in vulture/core.py, which I didn't touch). I believe this is flake8 and black fighting, but I didn't go too far down the rabbit hole and ended up using --no-verify.

It turns out this isn't a conflict with black, it's a change in flake8 between Python versions. When I run tox from a 3.12 virtualenv, the style check fails with:

tests/test_utils.py:146:32: E272 multiple spaces before keyword
vulture/config.py:119:69: E231 missing whitespace after ','
vulture/config.py:120:25: E231 missing whitespace after ','
vulture/config.py:120:30: E231 missing whitespace after ','
vulture/config.py:120:42: E231 missing whitespace after ','
vulture/config.py:130:59: E231 missing whitespace after ','
vulture/config.py:138:71: E231 missing whitespace after ','
vulture/core.py:158:41: E231 missing whitespace after ':'
vulture/core.py:172:50: E231 missing whitespace after ':'

When run from a 3.8 virtualenv, flake8 is happy. I was getting failures only from pre-commit because I had installed pre-commit from the 3.12 virtualenv and then switched virtualenvs.

It turns out that if you use pyenv and have pre-commit (or other utilities) installed with a Python it manages, it turns into a pain in the butt, so I ended up installing pre-commit via pipx with my system python (3.11.5). It turns out there is a bug in a recent version of flake8 that was fixed in 6.1.0.

tl;dr @jendrikseipp I think the fix is just to bump flake8 in tox.ini. Do you want a separate PR in the name of a clean changelog or should I just throw it in here?

[jendrikseipp]

Thanks for the changes and for looking into the flake8 issue! I'll merge this as is to have a clean history. Would be great if you could send another PR for the flake8 issue.