Infinite recursion when using namespace in home configuration

[Bear-03]

Hello.

I am trying to build a simple flake with snowfall, but when I try to use a namespaced module in my home configuration, I get the following error:

building the system configuration...
error:
       … while calling the 'head' builtin
         at /nix/store/4r8s42c9mwfvgdlxv0izb1cmlzrsb5nz-source/lib/attrsets.nix:1574:11:
         1573|         || pred here (elemAt values 1) (head values) then
         1574|           head values
             |           ^
         1575|         else

       … while evaluating the attribute 'value'
         at /nix/store/4r8s42c9mwfvgdlxv0izb1cmlzrsb5nz-source/lib/modules.nix:816:9:
          815|     in warnDeprecation opt //
          816|       { value = addErrorContext "while evaluating the option `${showOption loc}':" value;
             |         ^
          817|         inherit (res.defsFinal') highestPrio;

       … while evaluating the option `system.build.toplevel':

       … while evaluating definitions from `/nix/store/4r8s42c9mwfvgdlxv0izb1cmlzrsb5nz-source/nixos/modules/system/activation/top-level.nix':

       … while evaluating the option `assertions':

       … while evaluating definitions from `/nix/store/q1ss75nhmjiydyqw8lbzwbx7cqk8z0qq-source/nixos/common.nix':

       … while evaluating the module argument `namespace' in "/nix/store/9bwi858z3pzcgf9g40bwqvr52lz2zycd-s6wc8mk3jb8ja70aawm5s0ndmda1cyvh-source/homes/x86_64-linux/bear@nixos-laptop/default.nix":

       (stack trace truncated; use '--show-trace' to show the full, detailed trace)

       error: infinite recursion encountered
       at /nix/store/4r8s42c9mwfvgdlxv0izb1cmlzrsb5nz-source/lib/modules.nix:515:28:
          514|         addErrorContext (context name)
          515|           (args.${name} or config._module.args.${name})
             |                            ^
          516|       ) (functionArgs f);

I am fairly surprised this is happening since the flake is as small as it can get. Just a module, a home configuration file and a system configuration file; here's their contents:

# modules/home/foo/default.nix
{ namespace, lib, ... }:
with lib;
{
    options."${namespace}".foo = {
        enable = mkEnableOption "Foo";
    };
}

# homes/x64_86-linux/bear@nixos-laptop
{ pkgs, lib, namespace, ... }:
{
    "${namespace}".foo.enable = true;
    home.stateVersion = "24.05";
}

# systems/x64_84-linux/nixos-laptop
{ config, namespace, lib, pkgs, ... }:
{
    imports = [./hardware.nix];

    users.users."bear" = {
        isNormalUser = true;
    };

    system.stateVersion = "24.05";
}

# flake.nix
{
    description = "DataMarket's NixOS flake";

    inputs = {
        # Nix Packages
        nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";

        # Snowfall
        snowfall-lib = {
            url = "github:snowfallorg/lib";
            inputs.nixpkgs.follows = "nixpkgs";
        };

        # Home Manager
        home-manager = {
            url = "github:nix-community/home-manager/release-24.05";
            inputs.nixpkgs.follows = "nixpkgs";
        };
    };

    outputs = inputs: inputs.snowfall-lib.mkFlake {
        inherit inputs;
        src = ./.;

        channels-config = {
            allowUnfree = true;
        };
    };
};

If i change "${namespace}" to internal it works.

Thanks in advance.

[jakehamilton]

Ah I think this is an issue with using home-manager as a NixOS module. I checked and it looks like that path is the only one that does not pass down namespace. It absolutely should, this is a bug. We pass namespace to everything else, I am pretty sure that I missed this one instance.

https://github.com/snowfallorg/lib/blob/main/snowfall-lib/home/default.nix#L276

More clearly stated: when using home-manager as a NixOS module, home-manager needs to have namespace passed as a specialArg, but Snowfall Lib is not doing that.

[Bear-03]

Ah I see, thanks. Is this planned to be resolved? For now I can just hardcore the namespace, but I'd like to do it the correct way.

[jakehamilton]

It should be fixed in a future release, just depends on me or someone else having the time and energy to implement the change.