feat: assert on broken/unsupported config structures

lib/assertions.nix

@@ -0,0 +1,16 @@
+{
+  pkgs,
+  config,
+  lib,
+  ...
+}:
+with lib; let
+  cfg = config.vim;
+in {
+  assertions = mkMerge [
+    {
+      assertion = cfg.kommentary.enable;
+      message = "Kommentary has been deprecated in favor";
+    }
+  ];
+}

lib/default.nix

@@ -2,4 +2,8 @@
   dag = import ./dag.nix {inherit lib;};
   booleans = import ./booleans.nix {inherit lib;};
   types = import ./types {inherit lib;};
+
+  imports = [
+    ./assertions.nix
+  ];
 }

lib/module/default.nix

@@ -45,5 +45,14 @@ in {
 
   config = mkIf cfg.enable {
     home.packages = [set.neovim];
+
+    assertions = mkMerge [
+      mkIf
+      (config.programs.neovim-flake.enable)
+      {
+        assertion = !config.programs.neovim.enable;
+        message = "You cannot use neovim-flake together with vanilla neovim.";
+      }
+    ];
   };
 }