Hi!

While rebuilding the python related packages against the Python 3.15rc2 version we found that mercurial fails to build from source [1].

The error is:

body: size=503, sha1=2d8ce8bb3816603b9683a1804a5a02c11224cb01 (py39 !)
\+  body: size=503, sha1=37fff6d86b8569f8be21fcdf937a8ec8463251ca
    % zip and tar.gz disallowed should both give 403

This is due to the default compression level of gz changing.

To fix it, I applied the following upstream commits:
- Drop py38 check (test-archive: drop conditionnal outptu for Python3.8) [2]
- Update sha1 for py315 (test-archive: adapt output to Python 3.15)
- Add python versions (test: add more python version to hghave)

I've applied these fixes in the sandbox [5] to verify that it builds successfully, please consider applying the patch to support the upcoming 3.15 version.

Setting the severity to important for now. Once Python 3.15 is released, it will be added to python3-defaults and this bug will become release critical.

Happy hacking,

[1]: https://debusine.debian.net/debian/r-python-python3.15/artifact/4719448/
[2]: https://foss.heptapod.net/mercurial/mercurial-devel/-/commit/04486a79799e6cccdd499350e3e60bc4f53731fa
[3]: https://foss.heptapod.net/mercurial/mercurial-devel/-/commit/8d20ade7899f2fa61ff226f6d72eec560b1d3c20
[4]: https://foss.heptapod.net/mercurial/mercurial-devel/-/commit/4261e6bb01e94b686e068695b6d64dc88911f520
[5]: https://debusine.debian.net/debian/r-python-python3.15/