`fnmatch.translate` changed in an undocumented way in Python 3.14
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Description
Documentation
Since Python 3.14, fnmatch.translate appends a lowercase z, whilst 3.13 and below used an uppercase Z.
https://docs.python.org/3/library/fnmatch.html#fnmatch.translate makes no mention of this. Searching for fnmatch in https://docs.python.org/3/whatsnew/3.14.html only finds https://docs.python.org/3/whatsnew/3.14.html#fnmatch .
> uvx --python=3.13 python -c "import fnmatch; print(fnmatch.translate('foo*'))"
(?s:foo.*)\Z
> uvx --python=3.14 python -c "import fnmatch; print(fnmatch.translate('foo*'))"
(?s:foo.*)\z
(noticed in https://github.com/pypa/distutils/issues/381)
Edit:
After further research, the only mention I could find in "What's new in Python 3.14" is https://docs.python.org/3/whatsnew/3.14.html#re, which only says
Support
\zas a synonym for\Z
not that \z is now also used in place of \Z.
https://docs.python.org/3/howto/regex.html#more-metacharacters does mention that
\Z
The same as\z. For compatibility with old Python versions.
Up to you to see if this is worth acting upon. It did confuse me and I had a bit of a hard time finding reference for this change. But I understand if it's considered "implementation detail" and that distutils (setuptools)'s test validating a regex is too niche of a use-case to be worth documenting.
Linked PRs
- gh-144457
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