feat: add typings for the node bindings

Fixes #3072

cli/src/generate/grammar_files.rs

@@ -35,6 +35,7 @@ const BUILD_RS_TEMPLATE: &str = include_str!("./templates/build.rs");
 const CARGO_TOML_TEMPLATE: &str = include_str!("./templates/cargo.toml");
 
 const INDEX_JS_TEMPLATE: &str = include_str!("./templates/index.js");
+const INDEX_D_TS_TEMPLATE: &str = include_str!("./templates/index.d.ts");
 const JS_BINDING_CC_TEMPLATE: &str = include_str!("./templates/js-binding.cc");
 const BINDING_GYP_TEMPLATE: &str = include_str!("./templates/binding.gyp");
 
@@ -97,16 +98,21 @@ pub fn generate_grammar_files(
             let mut package_json = serde_json::from_str::<Map<String, Value>>(&package_json_str)
                 .with_context(|| "Failed to parse package.json")?;
             let package_json_main = package_json.get("main");
+            let package_json_types = package_json.get("types");
             let package_json_needs_update = package_json_main.map_or(true, |v| {
                 let main_string = v.as_str();
                 main_string == Some("index.js") || main_string == Some("./index.js")
-            });
+            }) || package_json_types.is_none();
             if package_json_needs_update {
                 eprintln!("Updating package.json with new binding path");
                 package_json.insert(
                     "main".to_string(),
                     Value::String("bindings/node".to_string()),
                 );
+                package_json.insert(
+                    "types".to_string(),
+                    Value::String("bindings/node".to_string()),
+                );
                 let mut package_json_str = serde_json::to_string_pretty(&package_json)?;
                 package_json_str.push('\n');
                 write_file(path, package_json_str)?;
@@ -193,6 +199,10 @@ pub fn generate_grammar_files(
                 generate_file(path, INDEX_JS_TEMPLATE, language_name)
             })?;
 
+            missing_path(path.join("index.d.ts"), |path| {
+                generate_file(path, INDEX_D_TS_TEMPLATE, language_name)
+            })?;
+
             missing_path_else(
                 path.join("binding.cc"),
                 |path| generate_file(path, JS_BINDING_CC_TEMPLATE, language_name),

cli/src/generate/templates/index.d.ts

@@ -0,0 +1,28 @@
+type BaseNode = {
+  type: string;
+  named: boolean;
+};
+
+type ChildNode = {
+  multiple: boolean;
+  required: boolean;
+  types: BaseNode[];
+};
+
+type NodeInfo =
+  | (BaseNode & {
+      subtypes: BaseNode[];
+    })
+  | (BaseNode & {
+      fields: { [name: string]: ChildNode };
+      children: ChildNode[];
+    });
+
+type Language = {
+  name: string;
+  language: unknown;
+  nodeTypeInfo: NodeInfo[];
+};
+
+declare const language: Language;
+export = language;

cli/src/generate/templates/package.json

@@ -4,6 +4,7 @@
   "description": "CAMEL_PARSER_NAME grammar for tree-sitter",
   "repository": "github:tree-sitter/tree-sitter-PARSER_NAME",
   "license": "MIT",
+  "types": "bindings/node",
   "main": "bindings/node",
   "files": [
     "grammar.js",