ci/eval/compare: mass rebuids will ping non-relevant maintainers

[balsoft]

Because of the way ci/eval/compare/maintainers.nix is implemented, if a mass-rebuild PR edits all-packages.nix, maintainers for a bunch of non-relevant packages will get pinged. Specifically, it will be packages which have their description, longDescription, maintainers, or teams set in all-packages.nix.

As a particular example, the @NixOS/security-review team was pinged in #431131 because it's listed as a team maintainer of git-doc, which was among the packages rebuilt and has its description set in all-packages.nix.

I see three ways to avoid/mitigate this:

1. Add an exception in maintainers.nix for all-packages.nix,
2. Move all description/longDescription/maintainers/teams settings out of all-packages.nix,
3. Change the "changed files" logic into a "changed file ranges" logic, to gracefully and correctly handle cases like this.

[eclairevoyant]

@NixOS/nixpkgs-ci would be relevant to ping here.

NixOS/rfcs#197 is possibly relevant if we find a way to generalise CI as per point 3

[mdaniels5757]

1 and 2 are possible, but don't really solve this problem except in the specific case of all-packages.nix. That is, e.g., python-packages.nix would still have this problem. I assume there are other files, perhaps not in pkgs/top-level, that have similar issues too. I would merge a PR that does either of these.

3 is not possible, I think, given the information that is available to us about definition locations. (I guess we could run a parser and try to find the complete definition, from the attrname, that the package maps to? But that would likely be IFD or something...)

I think the real solution here, though, is either something like RFC 197, or at least nixpkgs-vet support for additional by-name directories like my work in NixOS/nixpkgs-vet#180. I will be able to make progress on the latter once 25.11 goes out of support this month.

[Pandapip1]

What about suspending automatic pings if the number of people to be pinged exceeds the limit?

[mdaniels5757]

This is already done; the limit is 16. See

nixpkgs/ci/github-script/reviewers.js

Line 39 in bfa8339

if (user_maintainers.length + team_maintainers.length > 16) {

.