lib/modules: Report a good error when option tree has bare type

          loc = prefix ++ [name];

          defns = pushedDownDefinitionsByName.${name} or [];

          defns' = rawDefinitionsByName.${name} or [];

          optionDecls = filter (m: isOption m.options) decls;

          optionDecls = filter

            (m: m.options?_type

                && (m.options._type == "option"

                    || throwDeclarationTypeError loc m.options._type

                )

            )

            decls;

        in

          if length optionDecls == length decls then

            let opt = fixupOptionType loc (mergeOptionDecls loc decls);

          ) unmatchedDefnsByName);

    };

  throwDeclarationTypeError = loc: actualTag:

    let

      name = lib.strings.escapeNixIdentifier (lib.lists.last loc);

      path = showOption loc;

      depth = length loc;

      paragraphs = [

        "Expected an option declaration at option path `${path}` but got an attribute set with type ${actualTag}"

      ] ++ optional (actualTag == "option-type") ''

          When declaring an option, you must wrap the type in a `mkOption` call. It should look somewhat like:

              ${comment}

              ${name} = lib.mkOption {

                description = ...;

                type = <the type you wrote for ${name}>;

                ...

              };

        '';

      # Ideally we'd know the exact syntax they used, but short of that,

      # we can only reliably repeat the last. However, we repeat the

      # full path in a non-misleading way here, in case they overlook

      # the start of the message. Examples attract attention.

      comment = optionalString (depth > 1) "\n    # ${showOption loc}";

    in

    throw (concatStringsSep "\n\n" paragraphs);

  /* Merge multiple option declarations into a single declaration.  In

     general, there should be only one declaration of each option.

     The exception is the ‘options’ attribute, which specifies

  config.set \

  ./declare-set.nix ./declare-enable-nested.nix

# Options: accidental use of an option-type instead of option (or other tagged type; unlikely)

checkConfigError 'Expected an option declaration at option path .result. but got an attribute set with type option-type' config.result ./options-type-error-typical.nix

checkConfigError 'Expected an option declaration at option path .result.here. but got an attribute set with type option-type' config.result.here ./options-type-error-typical-nested.nix

checkConfigError 'Expected an option declaration at option path .result. but got an attribute set with type configuration' config.result ./options-type-error-configuration.nix

# Check that that merging of option collisions doesn't depend on type being set

checkConfigError 'The option .group..*would be a parent of the following options, but its type .<no description>. does not support nested options.\n\s*- option.s. with prefix .group.enable..*' config.group.enable ./merge-typeless-option.nix

{ lib, ... }: {

  options = {

    # unlikely mistake, but we can catch any attrset with _type

    result = lib.evalModules { modules = []; };

  };

}

{ lib, ... }: {

  options = {

    result.here = lib.types.str;

  };

}

{ lib, ... }: {

  options = {

    result = lib.types.str;

  };

}