feat: frontend unit tests

frontend/tests/utils/helpers/formatInnerLink.test.ts

@@ -0,0 +1,23 @@
+import { formatInnerLink } from '../../../src/static/js/utils/helpers/formatInnerLink';
+
+describe('js/utils/helpers', () => {
+    describe('formatInnerLink', () => {
+        test('Returns the same absolute URL unchanged', () => {
+            const url = 'https://example.com/path?x=1#hash';
+            const base = 'https://base.example.org';
+            expect(formatInnerLink(url, base)).toBe(url);
+        });
+
+        test('Constructs absolute URL from relative path with leading slash', () => {
+            const url = '/images/picture.png';
+            const base = 'https://media.example.com';
+            expect(formatInnerLink(url, base)).toBe('https://media.example.com/images/picture.png');
+        });
+
+        test('Constructs absolute URL from relative path without leading slash', () => {
+            const url = 'assets/file.txt';
+            const base = 'https://cdn.example.com';
+            expect(formatInnerLink(url, base)).toBe('https://cdn.example.com/assets/file.txt');
+        });
+    });
+});