add getAvailableLanguages() on TranslatorInterface.ts

Author: ArrayIterator

src/Translations/Interfaces/TranslatorInterface.ts

@@ -195,4 +195,10 @@ export default interface TranslatorInterface<
      * Clear the stored translations
      */
     clear() : void;
+
+    /**
+     * Get available languages within domain
+     * @param {string} domain - the translation domain
+     */
+    getAvailableLanguages(domain: string): string[];
 }

src/Translations/Translator.ts

@@ -329,4 +329,24 @@ export default class Translator<
         // emptying
         this.#translatorEntries = {};
     }
+
+    /**
+     * @inheritDoc
+     */
+    public getAvailableLanguages(domain: string): string[] {
+        if (!is_string(domain)) {
+            return [];
+        }
+        let languages: string[] = [];
+        if (!this.#translatorEntries[domain]) {
+            return languages;
+        }
+        for (let language in this.#translatorEntries[domain]) {
+            if (!this.#translatorEntries[domain].hasOwnProperty(language)) {
+                continue;
+            }
+            languages.push(language);
+        }
+        return languages
+    }
 }