The test-no-python-version test was failing because hatchling's
dependency on pathspec was incompatible with Python 3.9,
causing a TypeError during the build process.
Fixed by switching from hatchling to uv_build backend
(0.9.22-0.10.0 range) which is fully compatible with
Python 3.9. The uv.lock file is updated to reflect the
new build backend and latest compatible versions of dependencies.
setup-uv gets confused when there are backslashes in `requirements.txt`.
This changes the regex to ignore backslashes.
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Co-authored-by: axm2 <>
1. If defined use version input
2. If defined use uv-file input
3. If defined use pyproject-file input
4. Search for required-version in uv.toml in repo root
5. Search for required-version in pyproject.toml in repo root
6. Use latest
Closes: #215
