nix-store -qR $(nix-build '<nixpkgs>' -A git --no-out-link)

or

nix path-info -rSh $(nix-build '<nixpkgs>' -A git --no-out-link)

or this command (which nix people avoid generally because it creates files outside of the store):

nix-env -p /tmp/clean-profile -iA nixpkgs.git && nix-store -qR /tmp/clean-profile


# then

rm /tmp/clean-profile* 

# to get rid of the temp files

and here’s how I personally implemented a global gitignore on my system. This is a snippet of my git config with home-manager:

 {lib, pkgs, ... }:

  programs.git = {
    enable = true;

    ignores = [
      "*.bloop"
      "*.bsp"
      "*.metals"
      "*.metals.sbt"
      "*metals.sbt"
      "*.direnv"
      "*.envrc"
      "*hie.yaml" 
      "*.mill-version"
      "*.jvmopts"
      "build/" 
    ];
}