ci: add keep-sorted workflow; format and sort top-level/python-packages.nix

[katexochen]

keep-sorted is a language-agnostic formatter that sorts lines between two markers in a larger file.

This is a first step to use keep-sorted to enforce sorting in nixpkgs, adding a CI job and sorting python-packages.nix (as it had a quite uniform structure already). The nixfmt format comes in handy here, as the way blocks are formatted make it really easy for keep-sorted.

As the workflow has pull_request_target trigger, it won't run on this PR, I've tested it on my fork: https://github.com/katexochen/nixpkgs/actions/runs/13934128359/job/38998162445?pr=1

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandboxing enabled in nix.conf? (See Nix manual)
  • sandbox = relaxed
  • sandbox = true
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 25.05 Release Notes (or backporting 24.11 and 25.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

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[aforemny]

LGTM!

[infinisil]

In the future I hope that we can migrate all lists of packages to something like pkgs/by-name, but for now this looks like a good alternative.

LGTM, I'll merge!

[infinisil]

Oh, conflict to resolve. It would also be good to add the formatting commit to .git-blame-ignore-revs btw

[katexochen]

Oh, conflict to resolve.

Yes, getting this in without a conflict isn't easy. 😅

[katexochen]

In the future I hope that we can migrate all lists of packages to something like pkgs/by-name, but for now this looks like a good alternative.

I hope we can do so, but keep-sorted can do much more! It can sort markdown tables, large lists of buildInputs, ...

[nixpkgs-ci]

Backport failed for release-24.11, because it was unable to cherry-pick the commit(s).

Please cherry-pick the changes locally and resolve any conflicts.

git fetch origin release-24.11
git worktree add -d .worktree/backport-391087-to-release-24.11 origin/release-24.11
cd .worktree/backport-391087-to-release-24.11
git switch --create backport-391087-to-release-24.11
git cherry-pick -x 5f6f5e13ae0b6960cbf1be8aeb3d0048285a08d1 cb755af53647e28dd54d576c074ac8de7ad6fc73 60b30dd3164e656eb5ca049064781d14999fc77c 3b0f56da6197c20bbd56132654a9a1a424ddf743 fd14c067813572afc03ddbf7cdedc3eab5a59954

[wolfgangwalther]

Backport failed for release-24.11, because it was unable to cherry-pick the commit(s).

We should do a manual backport as well to avoid merge conflicts when backporting python packages.

[wolfgangwalther]

I think we should add fd14c06, i.e. the sorting commit, here, too.

[katexochen]

Done in #392717