DeprecationWarning for accessing attr.__version__

[timothygebhard]

Line 49 in canmatrix.py is giving me a DeprecationWarning:

DeprecationWarning: Accessing attr.__version__ is deprecated and will be removed in a future release. Use importlib.metadata directly to query for attrs's packaging metadata.
    if attr.__version__ < '17.4.0':  # type: ignore

I think fixing it should be as easy as:

from importlib.metadata import version

if version("attr") < '17.4.0':  # type: ignore
    raise RuntimeError("need attrs >= 17.4.0")

However, the attr package on PyPI currently only is at version 0.3.2, so this will always give a RuntimeError. Additionally, the error message refers to attrs (note the s at the end), and that's also what is required in the setup.py, so maybe it should be attrs everywhere instead of attr? 🙂

[ebroecker]

@timothygebhard
thanks for your report.

[ebroecker]

should be fixed