cups-pdf: misc improvements in package, module, vmtest

[Yarny0]

• cups-pdf-to-pdf package: remove with lib; from meta, drop unused rec, use lib.getExe and substituteInPlace
• cups-pdf vm test: migrate to runTest, use lib.getExe', avoid deprecated ${pkgs.imageMagick}/bin/convert program

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.

nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD" tries to rebuild 3000+ package and was therefore skipped.

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[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/prs-ready-for-review/3032/5289

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/prs-ready-for-review/3032/5323

[Yarny0]

Pushed a rebase due to #380990

[MattSturgeon]

imageMagickBig.meta.mainProgram is "magick", so we can use the non-prime getExe here:

Suggested change

	run(f"${lib.getExe' hostPkgs.imagemagickBig "magick"} -density 300 $out/{name}.pdf $out/{name}.jpeg", shell=True, check=True)
	run(f"${lib.getExe hostPkgs.imagemagickBig} -density 300 $out/{name}.pdf $out/{name}.jpeg", shell=True, check=True)

[MattSturgeon]

Would it be practical to use substituteInPlace and --replace-fail instead of sed here? Generally, this is preferred over using sed.

Something like:

Suggested change

	sed -r 's|(gscall, size, ")cp |\1${lib.getExe' coreutils "cp"} |' cups-pdf.c -i
	substituteInPlace cups-pdf.c \
	--replace-fail \
	'gscall, size, "cp ' \
	'gscall, size, "${lib.getExe' coreutils "cp"} '

or maybe even:

Suggested change

	sed -r 's|(gscall, size, ")cp |\1${lib.getExe' coreutils "cp"} |' cups-pdf.c -i
	substituteInPlace cups-pdf.c \
	--replace-fail \
	'"cp ' \
	'"${lib.getExe' coreutils "cp"} '

[Yarny0]

Done. Reducing the "discovery string" is a bit risky, but your suggestion still looks passable to me (I've also added an explanation to this effect to the commit message).

[Yarny0]

Rebased and applied suggestions by @MattSturgeon . Package still builds, cups-pdf-to-pdf.tests still pass.

[nixos-discourse]

This pull request has been mentioned on NixOS Discourse. There might be relevant details there:

https://discourse.nixos.org/t/prs-ready-for-review/3032/5390