lib.types.attrNamesTo{Set,Submodule}: addorigin/lib-types-attrNamesToTrue

3 files changed, 141 insertions, 0 deletions

diff --git a/lib/tests/modules/types.nix b/lib/tests/modules/types.nix
index 13c925853b98..8fa15ff8f5b9 100644
--- a/lib/tests/modules/types.nix
+++ b/lib/tests/modules/types.nix
@@ -7,6 +7,15 @@ let
     types
     mkOption
     ;
+
+  m = {
+    options = {
+      enableQux = mkOption {
+        type = types.bool;
+        default = false;
+      };
+    };
+  };
 in
 {
   options = {
@@ -14,6 +23,8 @@ in
     # NB: types are tested in multiple places, so this list is far from exhaustive
     pathInStore = mkOption { type = types.lazyAttrsOf types.pathInStore; };
     attrNamesToTrue = mkOption { type = types.lazyAttrsOf types.attrNamesToTrue; };
+    attrNamesToSet = mkOption { type = types.lazyAttrsOf types.attrNamesToSet; };
+    attrNamesToSubmodules = mkOption { type = types.lazyAttrsOf (types.attrNamesToSubmodules m); };
   };
   config = {
     pathInStore.ok1 = "${storeDir}/0lz9p8xhf89kb1c1kk6jxrzskaiygnlh-bash-5.2-p15.drv";
@@ -41,6 +52,40 @@ in
       b = false;
       c = true;
     };
+    attrNamesToSet.justNames = [
+      "a"
+      "b"
+      "c"
+    ];
+    attrNamesToSet.mixed = lib.mkMerge [
+      {
+        a = { };
+        b = { };
+      }
+      [ "c" ]
+    ];
+    attrNamesToSet.trivial = {
+      a = { };
+      b = { };
+      c = { };
+    };
+    attrNamesToSubmodules.justNames = [
+      "a"
+      "b"
+      "c"
+    ];
+    attrNamesToSubmodules.mixed = lib.mkMerge [
+      {
+        a = { };
+        b.enableQux = true;
+      }
+      [ "c" ]
+    ];
+    attrNamesToSubmodules.trivial = {
+      a = { };
+      b.enableQux = true;
+      c = { };
+    };
     check =
       assert
         config.attrNamesToTrue.justNames == {
@@ -60,6 +105,42 @@ in
           b = false;
           c = true;
         };
+      assert
+        config.attrNamesToSet.justNames == {
+          a = { };
+          b = { };
+          c = { };
+        };
+      assert
+        config.attrNamesToSet.mixed == {
+          a = { };
+          b = { };
+          c = { };
+        };
+      assert
+        config.attrNamesToSet.trivial == {
+          a = { };
+          b = { };
+          c = { };
+        };
+      assert
+        config.attrNamesToSubmodules.justNames == {
+          a.enableQux = false;
+          b.enableQux = false;
+          c.enableQux = false;
+        };
+      assert
+        config.attrNamesToSubmodules.mixed == {
+          a.enableQux = false;
+          b.enableQux = true;
+          c.enableQux = false;
+        };
+      assert
+        config.attrNamesToSubmodules.trivial == {
+          a.enableQux = false;
+          b.enableQux = true;
+          c.enableQux = false;
+        };
       "ok";
   };
 }
diff --git a/lib/types.nix b/lib/types.nix
index c0fcf5dae0c7..7b977f439afe 100644
--- a/lib/types.nix
+++ b/lib/types.nix
@@ -1463,6 +1463,16 @@ let
         enabledList: lib.genAttrs enabledList (_attrName: true)
       ) (types.attrsOf types.bool);
 
+      # Tests: lib/tests/modules.sh, lib/tests/modules/types.nix
+      # Docs: nixos/doc/manual/development/option-types.section.md
+      # Docs: https://nixos.org/manual/nixos/unstable/#sec-option-types-basic
+      attrNamesToSet = attrNamesToSubmodules { };
+      attrNamesToSubmodules =
+        m:
+        coercedTo (types.listOf types.str) (enabledList: lib.genAttrs enabledList (_attrName: { })) (
+          types.attrsOf (types.submodule m)
+        );
+
       # Augment the given type with an additional type check function.
       addCheck = elemType: check: elemType // { check = x: elemType.check x && check x; };
 
diff --git a/nixos/doc/manual/development/option-types.section.md b/nixos/doc/manual/development/option-types.section.md
index 8539da71a214..b144095c7153 100644
--- a/nixos/doc/manual/development/option-types.section.md
+++ b/nixos/doc/manual/development/option-types.section.md
@@ -143,6 +143,9 @@ merging is handled.
     convenient to be able to write definitions as a simple list, but
     still need to be able to override and disable individual values.
 
+    If configurability of the items is needed or `false` is not a
+    desirable value, prefer `types.attrNamesToSubmodule` or `types.attrNamesToSet`.
+
     ::: {#ex-types-attrNamesToTrue .example}
     ### `types.attrNamesToTrue`
     ```
@@ -158,6 +161,53 @@ merging is handled.
     ```
     :::
 
+`types.attrNamesToSet`
+
+:   Either a list of attribute names, or an attribute set of `{ }`.
+    This is similar to `types.attrNamesToTrue`, but `false` is not a permitted
+    value. This is useful when that's not an expected value, and by using this
+    type, you have the option to upgrade the type to `types.attrNamesToSubmodule`
+    without breaking anything.
+
+    ::: {#ex-types-attrNamesToSet .example}
+    ### `types.attrNamesToSet`
+    ```
+    {
+      foo = [ "bar" ];
+    }
+    ```
+
+    ```
+    {
+      foo.bar = { };
+    }
+    ```
+    :::
+
+`types.attrNamesToSubmodule` *`submodule`*
+
+:   Either a list of attribute names, or an attribute set of submodules.
+    This is similar to `types.attrNamesToSet`, but the values are submodules
+    instead of empty sets. This is useful when the values of this type are
+    optionally configurable.
+
+    ::: {#ex-types-attrNamesToSubmodule .example}
+    ### `types.attrNamesToSubmodule`
+    ```
+    {
+      foo = [ "bar" ];
+    }
+    ```
+
+    ```
+    {
+      foo.bar = { };
+      foo.baz.enableQux = true;
+    }
+    ```
+    :::
+
+
 `types.pkgs`
 
 :   A type for the top level Nixpkgs package set.