nix-community.nixvim/plugins/lsp/language-servers/vls.nix

{ lib, config, ... }:
with lib;
let
  cfg = config.plugins.lsp.servers.vls;
in
{
  options.plugins.lsp.servers.vls = {
    autoSetFiletype = mkOption {
      type = types.bool;
      description = ''
        Files with the `.v` extension are not automatically detected as vlang files.
        If this option is enabled, Nixvim will automatically set  the filetype accordingly.
      '';
      default = true;
      example = false;
    };
  };

  config = mkIf cfg.enable { filetype.extension = mkIf cfg.autoSetFiletype { v = "vlang"; }; };
}