flake-parts/setups: refactor NixVim integration

modules/flake-parts/setups/home-manager.nix

@@ -4,7 +4,6 @@
 let
   cfg = config.setups.home-manager;
   homeManagerModules = ../../home-manager;
-  partsConfig = config;
 
   # A thin wrapper around the home-manager configuration function.
   mkHome =
@@ -115,21 +114,6 @@ let
             home.homeDirectory = lib.mkForce setupConfig.homeDirectory;
           }
         )
-
-        (lib.mkIf (config.nixvim.instance != null)
-          ({ lib, ... }: {
-            imports = [
-              inputs.${config.nixvim.branch}.homeManagerModules.nixvim
-            ];
-
-            config.programs.nixvim = { ... }: {
-              enable = lib.mkDefault true;
-              imports =
-                partsConfig.setups.nixvim.configs.${config.nixvim.instance}.modules
-                ++ partsConfig.setups.nixvim.sharedModules
-                ++ config.nixvim.additionalModules;
-            };
-          }))
       ];
 
       nixpkgs.config = cfg.sharedNixpkgsConfig;
@@ -179,7 +163,6 @@ in
         modules = [
           (import ./shared/nix-conf.nix { inherit inputs; })
           ./shared/nixpkgs-options.nix
-          ./shared/nixvim-instance-options.nix
           ./shared/config-options.nix
           configType
         ];

modules/flake-parts/setups/nixos.nix

@@ -335,22 +335,6 @@ let
           }
         ))
 
-      # Next, we include the chosen NixVim configuration into NixOS.
-      (lib.mkIf (config.nixvim.instance != null)
-        (
-          { lib, ... }: {
-            imports = [ inputs.${config.nixvim.branch}.nixosModules.nixvim ];
-
-            programs.nixvim = { ... }: {
-              enable = lib.mkDefault true;
-              imports =
-                partsConfig.setups.nixvim.configs.${config.nixvim.instance}.modules
-                ++ partsConfig.setups.nixvim.sharedModules
-                ++ setupConfig.nixvim.additionalModules;
-            };
-          }
-        ))
-
       # Then we include the Disko configuration (if there's any).
       (lib.mkIf (config.diskoConfigs != [ ]) (
         let
@@ -413,7 +397,6 @@ in
         modules = [
           (import ./shared/nix-conf.nix { inherit inputs; })
           ./shared/config-options.nix
-          ./shared/nixvim-instance-options.nix
           ./shared/home-manager-users.nix
           ./shared/nixpkgs-options.nix
           configType

modules/flake-parts/setups/nixvim.nix

@@ -7,6 +7,7 @@
 }:
 
 let
+  partsConfig = config;
   cfg = config.setups.nixvim;
   nixvimModules = ../../nixvim;
 
@@ -106,6 +107,59 @@ let
       ];
     };
   };
+
+  nixvimIntegrationModule = { name, config, lib, ... }: {
+    options.nixvim = {
+      instance = lib.mkOption {
+        type = with lib.types; nullOr str;
+        default = null;
+        example = "fiesta";
+        description = ''
+          The name of the NixVim configuration from
+          {option}`setups.nixvim.configs.<name>` to be included as part
+          of the wider-scoped environment.
+        '';
+      };
+
+      branch = lib.mkOption {
+        type = lib.types.nonEmptyStr;
+        default = "nixvim";
+        example = "nixvim-stable";
+        description = ''
+          The branch of NixVim to be used for the module.
+
+          ::: {.tip}
+          A rule of thumb for properly setting up NixVim with the wider-scoped
+          environment is it should match the nixpkgs version of it. For example,
+          a NixOS system of `nixos-23.11` nixpkgs branch should be paired with a NixVim
+          branch of `nixos-23.11`.
+          :::
+        '';
+      };
+
+      additionalModules = lib.mkOption {
+        type = with lib.types; listOf raw;
+        default = [ ];
+        description = ''
+          A list of additional NixVim modules to be included.
+        '';
+      };
+    };
+
+    config = lib.mkIf (config.nixvim.instance != null) {
+      modules = [
+        ({ lib, ... }: {
+          programs.nixvim = { ... }: {
+            enable = lib.mkDefault true;
+            imports =
+              partsConfig.setups.nixvim.configs.${config.nixvim.instance}.modules
+              ++ partsConfig.setups.nixvim.sharedModules
+              ++ config.nixvim.additionalModules;
+          };
+        })
+      ];
+    };
+  };
 in
 {
   options.setups.nixvim = {
@@ -141,6 +195,28 @@ in
     };
   };
 
+  options.setups.nixos.configs = lib.mkOption {
+    type = with lib.types; attrsOf (submodule [
+      nixvimIntegrationModule
+      ({ config, lib, ... }: {
+        config.modules = [
+          inputs.${config.nixvim.branch}.nixosModules.nixvim
+        ];
+      })
+    ]);
+  };
+
+  options.setups.home-manager.configs = lib.mkOption {
+    type = with lib.types; attrsOf (submodule [
+      nixvimIntegrationModule
+      ({ config, lib, ... }: {
+        config.modules = [
+          inputs.${config.nixvim.branch}.homeManagerModules.nixvim
+        ];
+      })
+    ]);
+  };
+
   config = lib.mkIf (cfg.configs != { }) {
     setups.nixvim.sharedNixpkgsConfig = config.setups.sharedNixpkgsConfig;
 

modules/flake-parts/setups/shared/nixvim-instance-options.nix

@@ -1,38 +0,0 @@
-{ lib, ... }: {
-  options.nixvim = {
-    instance = lib.mkOption {
-      type = with lib.types; nullOr str;
-      default = null;
-      example = "fiesta";
-      description = ''
-        The name of the NixVim configuration from
-        {option}`setups.nixvim.configs.<name>` to be included as part
-        of the wider-scoped environment.
-      '';
-    };
-
-    branch = lib.mkOption {
-      type = lib.types.nonEmptyStr;
-      default = "nixvim";
-      example = "nixvim-stable";
-      description = ''
-        The branch of NixVim to be used for the module.
-
-        ::: {.tip}
-        A rule of thumb for properly setting up NixVim with the wider-scoped
-        environment is it should match the nixpkgs version of it. For example,
-        a NixOS system of `nixos-23.11` nixpkgs branch should be paired with a NixVim
-        branch of `nixos-23.11`.
-        :::
-      '';
-    };
-
-    additionalModules = lib.mkOption {
-      type = with lib.types; listOf raw;
-      default = [ ];
-      description = ''
-        A list of additional NixVim modules to be included.
-      '';
-    };
-  };
-}