lib/tests: Add submodule file propagation test

## Paths should be allowed as values and work as expected

checkConfigOutput '^true$' config.submodule.enable ./declare-submoduleWith-path.nix

# Check the file location information is propagated into submodules

checkConfigOutput the-file.nix config.submodule.internalFiles.0 ./submoduleFiles.nix

# Check that disabledModules works recursively and correctly

checkConfigOutput '^true$' config.enable ./disable-recursive/main.nix

checkConfigOutput '^true$' config.enable ./disable-recursive/{main.nix,disable-foo.nix}

{ lib, ... }: {

  options.submodule = lib.mkOption {

    default = {};

    type = lib.types.submoduleWith {

      modules = [ ({ options, ... }: {

        options.value = lib.mkOption {};

        options.internalFiles = lib.mkOption {

          default = options.value.files;

        };

      })];

    };

  };

  imports = [

    {

      _file = "the-file.nix";

      submodule.value = 10;

    }

  ];

}