So, it seems like PyPI has started taking a much stricter approach towards license metadata:
I can understand the intent, but getting this type of error at the end of our release procedure (which is, well, highly non-trivial) is a bit frustrating:
Uploading pyarrow-22.0.0.tar.gz
100% ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1.1/1.1 MB • 00:00 • 140.0 MB/s
WARNING Error during upload. Retry with the --verbose option for more details.
ERROR HTTPError: 400 Bad Request from https://upload.pypi.org/legacy/
License-File LICENSE.txt does not exist in distribution file pyarrow-22.0.0.tar.gz at pyarrow-22.0.0/LICENSE.txt
It would be nice if there was a way to PyPI-sanity-check a package before upload, such that we would detect such situations ahead of time and not at the last moment.