javascript: add corepack option

[nicknovitski]

# Before: 
{
  languages.javascript.enable = true;
  languages.javascript.package = pkgs.nodejs-16_x;
  packages = [ (pkgs.yarn.override { nodejs = pkgs.nodejs-16_x; }) ];
}

# Or alternatively:
{
  languages.javascript.enable = true;
  languages.javascript.package = pkgs.nodejs-16_x;
  scripts.yarn.exec = ''exec corepack yarn "$@"'';
}

# But with this change:
{
  languages.javascript.enable = true;
  languages.javascript.package = pkgs.nodejs-16_x;
  languages.javascript.corepack.enable = true;
}

[domenkozar]

Seems like you need to run pre-commit run -a

[nicknovitski]

~~> Setting up the default profile
  installing 'nix-2.13.3'
  error: unexpected EOF reading a line
  (use '--show-trace' to show detailed location information)

Since this happened on macos, I assume it's this: NixOS/nix#3605.

[tennox]

I'm curious if corepack brings any advantage over nix-native installing of package-managers, and if the problem described couldn't be fixed in a more nix-y way (and not installing package managers later via this shim, which is kinda bypassing nix & it's advantages) by adding package-manager selection & overlay handling to devenv's languages/javascript.nix instead.

Also, adding an overlay with the nodejs version selected might be a good idea so if users install e.g. yarn/pnpm, it will use the right version. 🤔

[shyim]

@tennox I guess it always depends on the team. If it's required to use Nix for the setup definitively Yes. But if an project have multiple setups, I guess this solution is okay. Also it's optional :)