various: clean up 'meta = with lib; { ... }'

[booxter]

This commit was generated using:

github.com:booxter/nix-clean_with-lib/fix-with-lib-in-meta@6540275

--- before.json	2025-09-13 22:06:30
+++ after.json	2025-09-13 22:08:39
@@ -826078,7 +826078,7 @@
       "maintainersPosition": {
         "column": 5,
         "file": "/Users/ihrachyshka/src/nixpkgs/pkgs/by-name/ep/epoll-shim/package.nix",
-        "line": 41
+        "line": 42
       },
       "name": "epoll-shim-0.0.20240608",
       "outputsToInstall": [

Some stats from one of the recent commit hashes:

$ git rev-parse --short HEAD
a85985a1a6cf

$ git grep 'meta = with ' | wc -l
504

$ git checkout HEAD~

$ git grep 'meta = with ' | wc -l
18294

$ python -c 'print(f"%.4f" % (504./18294))'
0.0276

The PR was specifically crafted to hit zero rebuilds to allow for mechanical validation. You can reproduce the patch using the generation script located here.

Note to reviewers: I'm sure this PR will clash with other patches. I am happy to refresh it when someone is ready to mechanically review the PR and merge it. Let me know!

Things done

• Built on platform:
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• Tested, as applicable:
  • NixOS tests in nixos/tests.
  • Package tests at passthru.tests.
  • Tests in lib/tests or pkgs/test for functions and "core" functionality.
• Ran nixpkgs-review on this PR. See nixpkgs-review usage.
• Tested basic functionality of all binary files, usually in ./result/bin/.
• Nixpkgs Release Notes
  • Package update: when the change is major or breaking.
• NixOS Release Notes
  • Module addition: when adding a new NixOS module.
  • Module update: when the change is significant.
• Fits CONTRIBUTING.md, pkgs/README.md, maintainers/README.md and other READMEs.

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[wolfgangwalther]

I don't feel confident reviewing / approving this, because I can't come up with a way to verify the exclusion list - there could be other files that are just left broken. Unfortunately nix-env -qa doesn't recurse into everything. Also the script is quite complex and hard to verify - what scares me a bit is the part where a sanity check with nixfmt is run and the change reverted if that doesn't pass. This means the transformation is not perfect - which also means there could be bad transformations that don't show up as a syntax error.

Maybe @philiptaron feels more confident about this.

[wolfgangwalther]

Here's a quick draft of a tiny first step of the approach I outlined on Matrix: technowledgy/refactor-tractor#14

Most of the code in there is glue and tests for the replacement. It's a rather simple treesitter query to replace only maintainers with lib.maintainers. The same can be done for various other fields easily. And then nixf-diagnose to clean up the unused with lib;. Personally, I'd trust that approach much more, because complexity of each step is much smaller.

[booxter]

@wolfgangwalther thanks for this. I'll take a look if I can instead contribute some rules there.

[booxter]

First stab at using Refactor Tractor for the same goal:

• treewide: clean up 'meta = with' pattern #443046
• lib-prefix: handle let; run for all files with meta = with lib; pattern; handle more attributes ({bad,hydra}Platforms; teams inside maintainers) technowledgy/refactor-tractor#15

@wolfgangwalther @philiptaron FYI

[booxter]

Gonna pursue the same via refactor-tractor: technowledgy/refactor-tractor#15