[issue22543] -W option cannot use non-standard categories

Michael Merickel added the comment: Updated affected versions as I ran into this on 3.9.7. -- nosy: +mmerickel versions: +Python 3.9 ___ Python tracker ___

[issue22543] -W option cannot use non-standard categories

Change by Omer Ozarslan : -- nosy: +ozars ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue22543] -W option cannot use non-standard categories

Change by Brett Cannon : -- nosy: -brett.cannon ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue22543] -W option cannot use non-standard categories

Feng Yu added the comment: Coming here from https://github.com/astropy/astropy/issues/9832#issuecomment-570751353 Importing the named module during warning initialization is somewhat like code injection. And it may introduce unintended side-effects -- for example if this causes some 3rd

[issue22543] -W option cannot use non-standard categories

Change by kernc : -- nosy: +kernc ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue22543] -W option cannot use non-standard categories

Gerrit Holl added the comment: There is a thread on StackOverflow related to this problem: https://stackoverflow.com/q/42495641/974555 The (currently only and accepted) answer proposes as a workaround to set the PYTHONPATH variable, as the contents of those apparently *are* already in

[issue22543] -W option cannot use non-standard categories

Change by Dmitry Shachnev : -- nosy: +mitya57 ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue22543] -W option cannot use non-standard categories

Change by Thrlwiti : -- nosy: +THRlWiTi ___ Python tracker ___ ___ Python-bugs-list mailing list Unsubscribe:

[issue22543] -W option cannot use non-standard categories

Torsten Landschoff added the comment: Wow, this was news to me and I just ran into it in python 2.7. Checked in Python 3 and it's still there: ``` (py3)->torsten.landschoff@horatio:~$ python3 --version Python 3.6.0a3+ (py3)->torsten.landschoff@horatio:~$ python3 -W

[issue22543] -W option cannot use non-standard categories

Brett Cannon added the comment: Doing the initialization later is not really an option as there can be warnings in the parser so it has to be resolved very early on. I guess some form could be a possibility, but that's also tricky as subclass matching also still needs to work. I think we

[issue22543] -W option cannot use non-standard categories

New submission from Rémi Rampin: warnings._processoptions is called very early, before site-packages are enabled. Because of this, using a non-standard 'category' will almost certainly fail with the message: Invalid -W option ignored: invalid module name: '...' The -W option would be a

[issue22543] -W option cannot use non-standard categories

Antoine Pitrou added the comment: How would this work? Would it auto-import the module? -- nosy: +brett.cannon, pitrou ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue22543 ___

[issue22543] -W option cannot use non-standard categories

Rémi Rampin added the comment: It already does auto-import, but it does it before site-packages are set up, meaning that it fails in any practical setup. See _getcategory(), called by _processoptions(): https://hg.python.org/cpython/file/b15c5a66213f/Lib/warnings.py#l148 --