Mypy (running in 3.10) complains that positional-only parameters are only supported in 3.8+

[hjwp]

Bug Report

To Reproduce

reporting based on current project, will try and find time for a minimal repro later, but in short:

• a python3.10 virtualenv with mypy and numpy (specific versions below)
• start mypy

Actual Behavior

👉  mypy /path/to/my_file.py
.venv/lib/python3.10/site-packages/numpy/__init__.pyi:642: error: Positional-only parameters are only supported in Python 3.8 and greater
Found 1 error in 1 file (errors prevented further checking)

I did also try adding an explict --python-version 3.10 flag, same result.

Your Environment

debian

• Mypy version used: mypy 0.971 (compiled: yes)
• Mypy command-line flags: (none)
• Mypy configuration options from mypy.ini (and other config files):

[tool.mypy]

[[tool.mypy.overrides]]
module = [
    "trimesh",
    "gmsh",
    "pyembree.*",
    "scipy.*",  # TODO: surely there are stubs for scipy somewhere?
]
ignore_missing_imports = true

• Python version used: Python 3.10.7
• Operating system and version: Debian bullseye
• numpy version 1.22.3

[AlexWaygood]

Duplicate of #13499, #13635, #13627. A fix will hopefully be out soon. Your best bet is to pin to Python 3.10.6 (not 3.10.7) until a mypy release with the fix is out.

[hjwp]

I'm so sorry, i should have searched more thoroughly for existing bugs. thanks for your help!

[TheNewThinkTank]

I am hit by the same issue. Running mypy from GitHub Actions, with Python 3.11, on ubuntu-latest. Link to failed run: https://github.com/TheNewThinkTank/Fitness-Tracker/actions/runs/4908617686/jobs/8764498089

[AlexWaygood]

I am hit by the same issue. Running mypy from GitHub Actions, with Python 3.11, on ubuntu-latest. Link to failed run: https://github.com/TheNewThinkTank/Fitness-Tracker/actions/runs/4908617686/jobs/8764498089

Looks like you're using a very old mypy: https://github.com/TheNewThinkTank/Fitness-Tracker/blob/422145d17167119d3a4bba75ed24548dcbeba50f/pyproject.toml#L12

Maybe try updating to the latest version (1.2.0)? :)

We fix bugs in every release of mypy. We don't backport bugfixes to older versions.

[TheNewThinkTank]

@AlexWaygood Thank you for the quick response. Updating mypy to version 1.2 fixed my issue.
for reference, https://github.com/TheNewThinkTank/Fitness-Tracker/actions/runs/4908775462/jobs/8764752729