jujutsu: update module to respect XDG config placement

[mrnossiom]

Description

Use the new supported XDG config place instead of home directory to make it cleaner

Checklist

• Change is backwards compatible.

• Code formatted with ./format.

• Code tested through nix-shell --pure tests -A run.all or nix develop --ignore-environment .#all using Flakes.

• Test cases updated/added. See example.

• Commit messages are formatted like

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  See CONTRIBUTING for more information and recent commit messages for examples.

@shikanime

[rycee]

Thanks! Merged to master now 🙂

[bnjmnt4n]

This breaks the configuration on macOS since Jujutsu does not currently support $XDG_CONFIG_HOME on macOS (see martinvonz/jj#3466, related: #5001).

For now, I'm adding the following to my configuration:

home.sessionVariables = lib.mkIf (pkgs.stdenv.hostPlatform.isDarwin) {
  JJ_CONFIG = "${config.xdg.configHome}/jj/config.toml";
};

I'm not sure what the recommended solution is here.

[mrnossiom]

It's possible to branch on isDarwin and place the config in the macOS standard directories. There seems to be a lot of discussion around following Apple guidelines for config placement, or just use XDG.

Follow-up PR : #5416