Drop support for EOL Python 3.9

[hugovk]

pip 26.1 already dropped support: pypa/pip#13905.

[henryiii]

I'd like to wait on this a bit, I don't want to drop two Python versions in one release (we just dropped 3.8).

[henryiii]

However, this was a perfect example to compare my drop Python skill against a traditional manual drop. I triggered this and then did a diff comparison with Claude:

🤖 AI text below 🤖

Both diffs are the same "Drop EOL Python 3.9" change, and the shared core is byte-for-byte identical. The differences are at the edges:

What's identical

Both make exactly the same edits to: perf.yml, test.yml, asv.conf.json, getting-started.rst, pyproject.toml (requires-python/classifier/mypy), noxfile.py (pypy3.9 removal), _parser.py, _ranges.py, markers.py, metadata.py, pylock.py, specifiers.py, utils.py, version.py, tasks/pickle_compat.py, tests/test_dependency_groups.py, tests/test_specifiers.py. That's the version-matrix drops plus the Union[...]→| / typing.Callable→collections.abc.Callable / drop sys.version_info TypeGuard/TypeAlias conditionals / zip(..., strict=False) cleanup.

Where they differ

1. docs.yml Python version

• Current → "3.10"
• PR Drop support for EOL Python 3.9 #1263 → "3.14"

(Both drop 3.9; they disagree on the replacement. PR picks the newest, current picks the new floor.)

2. PR #1263 also simplifies Generator[X, None, None] → Generator[X] — current does NOT touch these. Files only PR #1263 changes:

• src/packaging/_tokenizer.py
• src/packaging/errors.py (two signatures)
• tests/test_manylinux.py
• tests/test_musllinux.py
• noxfile.py second hunk (_replace_file return type)
• _manylinux.py: PR simplifies the _parse_elf Generator return type

3. _manylinux.py comment — opposite handling

• Current removes the stale # os.PathLike not a generic type until Python 3.9... comment but leaves the Generator[ELFFile | None, None, None] signature untouched.
• PR Drop support for EOL Python 3.9 #1263 keeps that (now-stale) comment but simplifies the signature to Generator[ELFFile | None].

4. CHANGELOG.rst — PR #1263 adds the "Drop support for EOL Python 3.9. (:pull:1263)" removal entry. Current has no changelog change.

5. src/packaging/licenses/_spdx.py — PR #1263 strips a leading blank line; current doesn't touch the file.

Net

PR #1263 is the more complete version: it also does the Generator[…, None, None] annotation simplification across the codebase, adds the changelog entry, and a stray _spdx.py cleanup. Your working tree is missing those, picks 3.10 instead of 3.14 for the docs build, and uniquely removes the stale os.PathLike comment (which PR #1263 left behind — arguably a small thing the PR should adopt).

[brettcannon]

There's some merge conflicts to fix.

[hugovk]

Conflicts resolved!

[henryiii]

Thanks! But I would still like to save this till after a release, we should probably try to push for a release soon.

[henryiii]

Hopefully, we'll release very soon, then this will be ready to merge a couple of days after that.

[hugovk]

Sorry, didn't mean to close this!

I'd made the PR on main because this repo prevents testing feature branches:

packaging/.github/workflows/test.yml

Lines 5 to 7 in 45a8b34

	push:
	branches:
	- main

And I want to make sure CI passes before opening a PR and pinging all the maintainers.

Then I forgot, and reset my main to upstream/main so GitHub closed it. Will try again :)

[hugovk]

Take two: #1354.

[henryiii]

You can also make a PR to your fork to get CI.

[hugovk]

Indeed, but that's also adding extra friction to contribution.