fix(nix): fix flake lock refresh

[SuperSandro2000]

Changes

This PR fixes flake.lock refreshes which didn't fully work in #31921 because of a testing oversight:

DEBUG: currentDigest not found in string to replace (repository=NuschtOS/ixx, branch=renovate/flake-inputs)
       "stringToReplace": "nixos-unstable",
       "currentDigest": "5df43628fdf08d642be8ba5b3625a6c70731c19c"
DEBUG: Starting search at index 55 (repository=NuschtOS/ixx, packageFile=flake.nix, branch=renovate/flake-inputs)
       "depName": "nixpkgs"
DEBUG: Found match at index 55 (repository=NuschtOS/ixx, packageFile=flake.nix, branch=renovate/flake-inputs)
       "depName": "nixpkgs"
DEBUG: Digest is not updated (repository=NuschtOS/ixx, packageFile=flake.nix, branch=renovate/flake-inputs)
       "depName": "nixpkgs",
       "manager": "nix",
       "expectedValue": "9d3ae807ebd2981d593cddd0080856873139aa40",
       "foundValue": "5df43628fdf08d642be8ba5b3625a6c70731c19c"
 WARN: Error updating branch: update failure (repository=NuschtOS/ixx, branch=renovate/flake-inputs)
DEBUG: syncBranchState() (repository=NuschtOS/ixx, branch=renovate/crates)

I used this to generate NuschtOS/ixx#54

The underlying problem is that renovate checks for the deps digest in the fileMatch which is for nix flakes the flake.lock. We need to keep the flake.nix otherwise the nixpkgs updater breaks. currentValue needed to be dropped because otherwise renovate would only search in there.

@mfenniak do you have a better idea?

Context

#31921 (comment)

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[SuperSandro2000]

I couldn't find a way to tell the updater here to check against the flake.lock file instead of the matched flake.nix file

[mfenniak]

I think this approach of matching on both the flake.nix and flake.lock file in the manager is a little ugly... the practical "problem" it will cause is that extractPackageFile is executed twice on a repo with both files, which you've aborted here, but not before it does work like reading the flake.lock file. That's pretty minor though. So as a minor code review, you could move packageLockFile & lockContents definitions to after the regex match.

I think one alternative approach would be something like this (main...mfenniak:renovate:fix-nix-alternative):

• match on just flake.nix as previously done
• if the regex match is hit and nixpkgs gets inserted into deps, then, skip depName == "nixpkgs" in the flake.lock loop

I think that would avoid the problem, if I've understood your change correctly -- there won't be any duplicate nixpkgs deps in this case -- and it might be a little easier to follow the code flow with this branch.

It would probably have a bug though: if nixpkgsRegex is matched on flake.nix, but it doesn't represent nixpkgs's input (could match a comment in the file, other content, or could match an input with another name eg. nixpkgs_24_04.input.url = "github:nixos/nixpkgs-24.04"), then... I'm not sure what the behavior would be actually. The depName and the actual dependency wouldn't match, and then the real nixpkgs dep (if present in the flake.lock) wouldn't be included... but I guess this is more of a latent bug with the existing regex match rather than a new problem. 🙁

[SuperSandro2000]

That didn't work out as expected :/

now other flake dependencies where detected twice

and somehow the artifactUpdate function is no longer run...

[SuperSandro2000]

and somehow the artifactUpdate function is no longer run...

I think that was because I dropped the currentValue and somehow created ghost updates that didn't really where there...

Oh boy... :notlikethis:

---

I have deployed the latest commit as of writing. This "ghost" PR got marked as abandon. NuschtOS/ixx#55 . Before with the commit from yesterday with this branch it pushed the entire day nonsense. See that PRs history. This dashboard is created with it NuschtOS/ixx#3 , too.

Also NuschtOS/search.nuschtos.de#44