Nixpkgs defaultLocale is not set by NixOS defaultLocale.

[nbp]

Forwarding issue from: https://mamot.fr/@yom/99932015049044453

Issue description

The problem is that NixOS configuration i18n.defaultLocale is not being transfered to Nixpkgs config. Therefore installing firefox-bin package as part of the default set of packages would select en_US instead of the one corresponding to the default locale.

Steps to reproduce

Add NixOS option i18n.defaultLocale to "fr_FR.UTF-8".
Add pkgs.firefox-bin as part of the environment.systemPackages.
$ nixos-rebuild switch
$ firefox
--> Firefox should be in French.

Technical details

We should probably add something like the following and ensure that the defaultLocale is processed properly as part of the minimal set of packages needed to evaluate the pkgs argument.

{config, ...}:

{ nixpkgs.config = {
    i18n.defaultLocale = config.i18n.defaultLocale;
  };
}

[matthewbauer]

So I didn't even realize that config.i18n.defaultLocale existed. Is there any documentation for it? I'm interested in standardizing these configs in Nixpkgs (#39580). In some ways it overlaps with the NixOS module system.

[FlorentBecker]

This seems to be because the firefox package does not come with any language packs.

[stale]

Thank you for your contributions.

This has been automatically marked as stale because it has had no activity for 180 days.

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