feat: add lua treesitter & lsp

modules/languages/lua.nix

@@ -0,0 +1,62 @@
+{
+  pkgs,
+  config,
+  lib,
+  ...
+}:
+with lib;
+with builtins; let
+  cfg = config.vim.languages.go;
+
+  defaultServer = "lua-ls";
+  servers = {
+    lua-ls = {
+      package = pkgs.lua-language-server;
+      lspConfig = ''
+        lspconfig.lua_ls.setup {
+          capabilities = capabilities;
+          on_attach = default_on_attach;
+          cmd = ${
+          if isList cfg.lsp.package
+          then nvim.lua.expToLua cfg.lsp.package
+          else ''{"${getExe cfg.lsp.package}"}''
+        };
+        }
+      '';
+    };
+  };
+in {
+  options.vim.languages.lua = {
+    treesitter = {
+      enable = mkOption "Enable Lua Treesitter support" // {default = config.vim.languages.enableTreesitter;};
+      package = nvim.types.mkGrammarOption pkgs "lua";
+    };
+    lsp = {
+      enable = mkOption "Enable Lua LSP support" // {default = config.vim.languages.enableLSP;};
+
+      server = mkOption {
+        description = "Lua LSP server to use";
+        type = with types; enum (attrNames servers);
+        default = defaultServer;
+      };
+
+      package = mkOption {
+        description = "Lua LSP server package, or the command to run as a list of strings";
+        type = with types; either package (listOf str);
+        default = servers.${cfg.lsp.server}.package;
+      };
+    };
+  };
+
+  config = mkIf cfg.enable (mkMerge [
+    (mkIf cfg.lsp.enable {
+      vim.lsp.lspconfig.enable = true;
+      vim.lsp.lspconfig.sources.lua-lsp = servers.${cfg.lsp.server}.lspConfig;
+    })
+
+    (mkIf cfg.treesitter.enable {
+      vim.treesitter.enable = true;
+      vim.treesitter.grammars = [cfg.treesitter.package];
+    })
+  ]);
+}