lib.makeOverridable: preserve constructor override and metadata attributes

[ShamrockLee]

Description

The local lib.makeOverridable for fetchers (added by PR #158968) drops the metadata attributes lib.extendMkDerivationattaches to the fetchers.

This PR fixes lib.makeOverridable to preserve the additional attributes. when the function to decorate is a callable attribute set.

Background

During the pre-finalAttrs era, PR #158968 uses lib.makeOverridable to add a custom overrider override to the result FOD of several fetchers in order to workaround the limitation of <pkg>.overrideAttrs.

However, lib.makeOverride was initially designed to be used by callPackage and provide the typical <pkg>.override interface, which doesn't take into account functions that has already been called with callPackage or callable attribute set containing extra attribuets (e.g., the ones defined with lib.extendMkDerivation).

Considering that those custom overriders will stay in Nixpkgs for quite some time, lib.makeOverridable should be able to handle those edge cases.

Quick validation

• Evaluate pkgs.fetchgit. After this change, the lib.extendMkDerivation-provided metadata attributes (constructDrv, excludeDrvArgNames, extendDrvArgs, transformDrv) will show up.

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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Add a 👍 reaction to pull requests you find important.

[ShamrockLee]

nixpkgs-review result

Generated using nixpkgs-review-gha

Command: nixpkgs-review pr 461032
Commit: d4eb6bcfb4f6f234ee13413546b441fc99391e6e (subsequent changes)
Merge: 81327c1b4d1007d8a5f54d9f9dcecf53de86c6df

Logs: https://github.com/ShamrockLee/nixpkgs-review-gha/actions/runs/19313832710

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x86_64-linux

⏩ 2 packages blacklisted:

• nixos-install-tools
• tests.nixos-functions.nixos-test

✅ 3 packages built:

• extra-container
• nixos-container
• nixpkgs-manual

---

aarch64-linux

⏩ 2 packages blacklisted:

• nixos-install-tools
• tests.nixos-functions.nixos-test

✅ 3 packages built:

• extra-container
• nixos-container
• nixpkgs-manual

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x86_64-darwin (sandbox = relaxed)

✅ 1 package built:

• nixpkgs-manual

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aarch64-darwin (sandbox = relaxed)

✅ 1 package built:

• nixpkgs-manual

[ShamrockLee]

Test cases added.

[roberth]

I despise this function, but until we replace it with a simpler concept, we may as well try and make the most of it.

[roberth]

The tests are much appreciated ❤️