add tsd tests and inspired fixes (making arguments optional)

Author: brettz9

packages/espree/espree.js

@@ -176,7 +176,7 @@ const parsers = {
 
     /**
      * Gets the parser object based on the supplied options.
-     * @param {Options} options The parser options.
+     * @param {Options} [options] The parser options.
      * @returns {EspreeParserJsxCtor|EspreeParserCtor} Regular or JSX Acorn parser
      */
     get(options) {
@@ -197,7 +197,7 @@ const parsers = {
 /**
  * Tokenizes the given code.
  * @param {string} code The code to tokenize.
- * @param {Options} options Options defining how to tokenize.
+ * @param {Options} [options] Options defining how to tokenize.
  * @returns {EspreeTokens} An array of tokens.
  * @throws {EnhancedSyntaxError} If the input code is invalid.
  * @private
@@ -220,7 +220,7 @@ export function tokenize(code, options) {
 /**
  * Parses the given code.
  * @param {string} code The code to tokenize.
- * @param {Options} options Options defining how to tokenize.
+ * @param {Options} [options] Options defining how to tokenize.
  * @returns {acorn.Node} The "Program" AST node.
  * @throws {EnhancedSyntaxError} If the input code is invalid.
  */

packages/espree/lib/espree.js

@@ -159,7 +159,7 @@ export default () => {
         return class Espree extends Parser {
 
             /**
-             * @param {Options | null} opts The parser options
+             * @param {Options | null | undefined} opts The parser options
              * @param {string | object} code The code which will be converted to a string.
              */
             constructor(opts, code) {

packages/espree/lib/types.js

@@ -28,12 +28,12 @@
 /* eslint-disable jsdoc/valid-types -- Bug in older versions */
 /**
  * @typedef {{
- *   new (opts: Options | null, code: string | object): EspreeParser
+ *   new (opts: Options | null | undefined, code: string | object): EspreeParser
  * } & Pick<typeof acorn.Parser, keyof typeof acorn.Parser>} EspreeParserCtor
  */
 /**
  * @typedef {{
- *   new (opts: Options | null, code: string | object): EspreeParser
+ *   new (opts: Options | null | undefined, code: string | object): EspreeParser
  * } & Pick<AcornJsxParserCtor, keyof AcornJsxParserCtor>} EspreeParserJsxCtor
  */
 

packages/espree/package.json

@@ -48,6 +48,7 @@
     "@rollup/plugin-node-resolve": "^15.3.0",
     "rollup": "^2.79.1",
     "shelljs": "^0.8.5",
+    "tsd": "^0.33.0",
     "typescript": "^5.9.3"
   },
   "keywords": [
@@ -67,7 +68,8 @@
     "build:update-version": "node tools/update-version.js",
     "prepublishOnly": "npm run build:update-version && npm run build",
     "pretest": "npm run build",
-    "test": "npm run test:cjs && npm run test:esm",
+    "test": "npm run test:tsd && npm run test:cjs && npm run test:esm",
+    "test:tsd": "tsd --typings dist/espree.d.ts",
     "test:cjs": "mocha --color --reporter progress --timeout 30000 \"tests/**/*.test.cjs\"",
     "test:esm": "c8 mocha --color --reporter progress --timeout 30000 \"tests/**/*.test.js\""
   }

packages/espree/test-d/index.test-d.ts

@@ -0,0 +1,53 @@
+import { expectType } from 'tsd';
+
+import * as espree from "../espree.js";
+import type { Options, EspreeTokens } from "../espree.js";
+import type {VisitorKeys} from "../../eslint-visitor-keys/lib/index.js";
+
+const ast = espree.parse("let foo = \"bar\"");
+expectType<acorn.Node>(ast);
+
+const ast_option = espree.parse("let foo = \"bar\"", { ecmaVersion: 6 });
+expectType<acorn.Node>(ast_option);
+
+const tokens = espree.tokenize("let foo = \"bar\"");
+expectType<EspreeTokens>(tokens);
+
+const tokens_option = espree.tokenize("let foo = \"bar\"", { ecmaVersion: 6 });
+expectType<EspreeTokens>(tokens_option);
+
+const version = espree.version;
+expectType<string>(version);
+
+const visitor_keys = espree.VisitorKeys;
+expectType<VisitorKeys>(visitor_keys);
+
+const latest_ecma = espree.latestEcmaVersion;
+expectType<number>(latest_ecma);
+
+const supported_ecma = espree.supportedEcmaVersions;
+expectType<number[]>(supported_ecma);
+
+const full_options: Options = {
+    range: false,
+    loc: false,
+    comment: false,
+    tokens: false,
+    ecmaVersion: 3,
+    allowReserved: true,
+    sourceType: "script",
+    ecmaFeatures: {
+        jsx: false,
+        globalReturn: false,
+        impliedStrict: false,
+    },
+};
+expectType<Options>(full_options);
+
+const empty_options: Options = {};
+expectType<Options>(empty_options);
+
+const latest_options: Options = {
+    ecmaVersion: 16,
+};
+expectType<Options>(latest_options);