Implement flag to allow typechecking of untyped modules by DeinAlptraum · Pull Request #17712

Implement flag to allow typechecking of untyped modules by DeinAlptraum · Pull Request #17712 · python/mypy

I tried this flag for Home Assistant today. Unfortunately, mypy couldn't even do a full run and failed instantly. Haven't narrowed it down completely yet, just a first reproducer (tested with Python 3.13):

# test.py
import aprslib.base91
reveal_type(1)

# mypy_config.ini
[mypy]
follow_imports = normal
follow_untyped_imports = true

pip install aprslib==0.7.2
mypy --config-file mypy_config.ini test.py

/.../venv/lib/python3.13/site-packages/aprslib/parsing/common.py:218: SyntaxWarning: invalid escape sequence '\!'
  match = re.findall("^(.*)\!([\x21-\x7b])([\x20-\x7b]{2})\!(.*?)$", body)
venv/lib/python3.13/site-packages/aprslib/parsing/__init__.py: error:
    Source file found twice under different module names: "aprslib.parsing" and "aprslib.parsing.__init__"
Found 1 error in 1 file (errors prevented further checking)

The SyntaxWarning is an unrelated issue.

Will open a new issue, once I've narrowed it down a bit more.