test: add localization tests

__tests__/localization.test.ts

@@ -0,0 +1,23 @@
+import { describe, it, expect, jest, beforeEach } from "bun:test";
+import { extractLocaleFromURL } from '../src/content/utils/localization'
+
+beforeEach(() => {
+  jest.clearAllMocks()
+})
+
+describe('localization', () => {
+  it('should assume `en` if no locale is specified', async () => {
+    // extractLocaleFromURL('https://wiki.teamfortress.com/wiki/Team_Fortress_2') should return 'en'
+    expect(extractLocaleFromURL('https://wiki.teamfortress.com/wiki/Team_Fortress_2')).toBe('en')
+  })
+
+  it('should extract locale shortcode from URL correctly', async () => {
+    // extractLocaleFromURL('https://wiki.teamfortress.com/wiki/Phlogistinator/de') should return 'de'
+    expect(extractLocaleFromURL('https://wiki.teamfortress.com/wiki/Phlogistinator/de')).toBe('de')
+  })
+
+  it('should extract locale shortcode with special characters from URL correctly', async () => {
+    // extractLocaleFromURL('https://wiki.teamfortress.com/wiki/%C3%9CberCharge/zh-hans') should return 'zh-hans'
+    expect(extractLocaleFromURL('https://wiki.teamfortress.com/wiki/%C3%9CberCharge/zh-hans')).toBe('zh-hans')
+  })
+})