feat: add treesitter textobjects

modules/plugins/treesitter/ts-textobjects/config.nix

@@ -0,0 +1,23 @@
+{
+  config,
+  lib,
+  ...
+}: let
+  inherit (lib.modules) mkIf;
+  inherit (lib.nvim.lua) toLuaObject;
+  inherit (lib.nvim.dag) entryAfter;
+
+  inherit (config.vim) treesitter;
+  cfg = treesitter.textobjects;
+in {
+  config = mkIf (treesitter.enable && cfg.enable) {
+    vim = {
+      startPlugins = ["nvim-treesitter-textobjects"];
+
+      # set up treesitter-textobjects after Treesitter, whose config we're adding to.
+      pluginRC.treesitter-textobjects = entryAfter ["treesitter"] ''
+        require("nvim-treesitter.configs").setup({textobjects = ${toLuaObject cfg.setupOpts}})
+      '';
+    };
+  };
+}

modules/plugins/treesitter/ts-textobjects/default.nix

@@ -0,0 +1,6 @@
+{
+  imports = [
+    ./textobjects.nix
+    ./config.nix
+  ];
+}

modules/plugins/treesitter/ts-textobjects/textobjects.nix

@@ -0,0 +1,21 @@
+{lib, ...}: let
+  inherit (lib.options) mkEnableOption;
+  inherit (lib.nvim.types) mkPluginSetupOption;
+in {
+  options.vim.treesitter.textobjects = {
+    enable = mkEnableOption "Treesitter textobjects";
+    setupOpts =
+      mkPluginSetupOption "treesitter-textobjects" {}
+      // {
+        example = {
+          select = {
+            enable = true;
+            lookahead = true;
+            keymaps = {
+              af = "@function.outer";
+            };
+          };
+        };
+      };
+  };
+}