Commit 118bdf25 authored by Robert Hensing's avatar Robert Hensing
Browse files

lib/modules: Allow an "anonymous" module with key in disabledModules 

This makes the following work

    disabledModules = [ foo.nixosModules.bar ];

even if `bar` is not a path, but rather a module such as

    { key = "/path/to/foo#nixosModules.bar"; config = ...; }

By supporting this, the user will often be able to use the same syntax
for both importing and disabling a module. This is becoming more relevant
because flakes promote the use of attributes to reference modules. Not
all of these modules in flake attributes will be identifiable, but with
the help of a framework such as flake-parts, these attributes can be
guaranteed to be identifiable (by outPath + attribute path).
parent 82b4c247

lib/modules.nix

+29 −5
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ let 
    isBool

    isFunction

    isList

    isPath

    isString

    length

    mapAttrs
@@ -45,6 +46,9 @@ let 
    showOption

    unknownModule

    ;

  inherit (lib.strings)

    isConvertibleWithToString

    ;



  showDeclPrefix = loc: decl: prefix:

    " - option(s) with prefix `${showOption (loc ++ [prefix])}' in module `${decl._file}'";
@@ -403,7 +407,7 @@ rec { 
            key = module.key;

            module = module;

            modules = collectedImports.modules;

            disabled = module.disabledModules ++ collectedImports.disabled;

            disabled = (if module.disabledModules != [] then [{ file = module._file; disabled = module.disabledModules; }] else []) ++ collectedImports.disabled;

          }) initialModules);



      # filterModules :: String -> { disabled, modules } -> [ Module ]
@@ -412,10 +416,30 @@ rec { 
      # modules recursively. It returns the final list of unique-by-key modules

      filterModules = modulesPath: { disabled, modules }:

        let

          moduleKey = m: if isString m && (builtins.substring 0 1 m != "/")

            then toString modulesPath + "/" + m

            else toString m;

          disabledKeys = map moduleKey disabled;

          moduleKey = file: m:

            if isString m

            then

              if builtins.substring 0 1 m == "/"

              then m

              else toString modulesPath + "/" + m



            else if isConvertibleWithToString m

            then

              if m?key && m.key != toString m

              then

                throw "Module `${file}` contains a disabledModules item that is an attribute set that can be converted to a string (${toString m}) but also has a `.key` attribute (${m.key}) with a different value. This makes it ambiguous which module should be disabled."

              else

                toString m



            else if m?key

            then

              m.key



            else if isAttrs m

            then throw "Module `${file}` contains a disabledModules item that is an attribute set, presumably a module, that does not have a `key` attribute. This means that the module system doesn't have any means to identify the module that should be disabled. Make sure that you've put the correct value in disabledModules: a string path relative to modulesPath, a path value, or an attribute set with a `key` attribute."

            else throw "Each disabledModules item must be a path, string, or a attribute set with a key attribute, or a value supported by toString. However, one of the disabledModules items in `${toString file}` is none of that, but is of type ${builtins.typeOf m}.";



          disabledKeys = concatMap ({ file, disabled }: map (moduleKey file) disabled) disabled;

          keyFilter = filter (attrs: ! elem attrs.key disabledKeys);

        in map (attrs: attrs.module) (builtins.genericClosure {

          startSet = keyFilter modules;

lib/tests/modules.sh

+12 −0
Original line number Diff line number Diff line
@@ -141,6 +141,14 @@ checkConfigError "The option .*enable.* does not exist. Definition values:\n\s*- 
checkConfigError "attribute .*enable.* in selection path .*config.enable.* not found" "$@" ./disable-define-enable.nix ./disable-declare-enable.nix

checkConfigError "attribute .*enable.* in selection path .*config.enable.* not found" "$@" ./disable-enable-modules.nix



checkConfigOutput '^true$' 'config.positive.enable' ./disable-module-with-key.nix

checkConfigOutput '^false$' 'config.negative.enable' ./disable-module-with-key.nix

checkConfigError 'Module ..*disable-module-bad-key.nix. contains a disabledModules item that is an attribute set, presumably a module, that does not have a .key. attribute. .*' 'config.enable' ./disable-module-bad-key.nix



# Not sure if we want to keep supporting module keys that aren't strings, paths or v?key, but we shouldn't remove support accidentally.

checkConfigOutput '^true$' 'config.positive.enable' ./disable-module-with-toString-key.nix

checkConfigOutput '^false$' 'config.negative.enable' ./disable-module-with-toString-key.nix



# Check _module.args.

set -- config.enable ./declare-enable.nix ./define-enable-with-custom-arg.nix

checkConfigError 'while evaluating the module argument .*custom.* in .*define-enable-with-custom-arg.nix.*:' "$@"
@@ -358,6 +366,10 @@ checkConfigOutput '^"The option `a\.b. defined in `.*/doRename-warnings\.nix. ha 
  config.result \

  ./doRename-warnings.nix



# Anonymous modules get deduplicated by key

checkConfigOutput '^"pear"$' config.once.raw ./merge-module-with-key.nix

checkConfigOutput '^"pear\\npear"$' config.twice.raw ./merge-module-with-key.nix



cat <<EOF

====== module tests ======

$pass Pass

lib/tests/modules/disable-module-bad-key.nix

0 → 100644
+16 −0
Original line number Diff line number Diff line 
{ lib, ... }:

let

  inherit (lib) mkOption types;



  moduleWithKey = { config, ... }: {

    config = {

      enable = true;

    };

  };

in

{

  imports = [

    ./declare-enable.nix

  ];

  disabledModules = [ { } ];

}

lib/tests/modules/disable-module-with-key.nix

0 → 100644
+34 −0
Original line number Diff line number Diff line 
{ lib, ... }:

let

  inherit (lib) mkOption types;



  moduleWithKey = {

    key = "disable-module-with-key.nix#moduleWithKey";

    config = {

      enable = true;

    };

  };

in

{

  options = {

    positive = mkOption {

      type = types.submodule {

        imports = [

          ./declare-enable.nix

          moduleWithKey

        ];

      };

      default = {};

    };

    negative = mkOption {

      type = types.submodule {

        imports = [

          ./declare-enable.nix

          moduleWithKey

        ];

        disabledModules = [ moduleWithKey ];

      };

      default = {};

    };

  };

}

lib/tests/modules/disable-module-with-toString-key.nix

0 → 100644
+34 −0
Original line number Diff line number Diff line 
{ lib, ... }:

let

  inherit (lib) mkOption types;



  moduleWithKey = {

    key = 123;

    config = {

      enable = true;

    };

  };

in

{

  options = {

    positive = mkOption {

      type = types.submodule {

        imports = [

          ./declare-enable.nix

          moduleWithKey

        ];

      };

      default = {};

    };

    negative = mkOption {

      type = types.submodule {

        imports = [

          ./declare-enable.nix

          moduleWithKey

        ];

        disabledModules = [ 123 ];

      };

      default = {};

    };

  };

}