part1

src/store/lang/getByIso639.js

@@ -1,18 +1,18 @@
 import { GET_BY_ISO639 } from '../../sql/language.js';
 import request from '../request.js';
 
-/**
- * Returns a language row by its ISO 639 code.
- *
- * @param {object} pool - The mssql connection pool.
- * @returns {Function} An async function that fetches a language by ISO code.
- *
- * @example
- * const fn = getByIso639(pool);
- * const lang = await fn('de');
- * // => { id, iso639 }
- */
 export default function getByIso639(pool) {
+  /**
+   * Returns a language row by its ISO 639 code.
+   *
+   * @param {string} iso639 - The ISO 639 language code (e.g. `'de'`).
+   * @param {object} [tx] - Optional transaction to run within.
+   * @returns {Promise<{id: number, iso639: string}>} The language row, or `undefined` if not found.
+   *
+   * @example
+   * const lang = await store.lang.getByIso639('de');
+   * // => { id: 1, iso639: 'de' }
+   */
   return async (iso639, tx) => {
     const result = await request(pool, tx)
       .input('iso639', iso639)