localization-testing

# Localization & Internationalization Testing <default_to_action> When testing multi-language/region support: 1. VERIFY translation coverage (all strings translated) 2. TEST locale-specific formats (date, time, currency, numbers) 3. VALIDATE RTL layout (Arabic, Hebrew) 4. CHECK character encoding (UTF-8, unicode) 5. CONFIRM cultural appropriateness (icons, colors, content) **Quick i18n Checklist:** - All user-facing strings externalized - No hardcoded text in code - Date/time/currency formatted per locale - RTL languages flip layout correctly - Unicode characters display properly **Critical Success Factors:** - Don't hardcode strings - externalize everything - Test with real speakers, not just translation files - RTL requires mirrored UI layout </default_to_action> ## Quick Reference Card ### When to Use - Launching in new markets - Adding language support - Before international releases - After UI changes ### i18n vs l10n | Term | Full Name | Focus | |------|-----------|-------| | **i18n** | Internationalization | Building for localization | | **l10n** | Localization | Adapting for specific locale | ### Common Locale Formats | Type | US (en-US) | UK (en-GB) | Japan (ja-JP) | |------|------------|------------|---------------| | **Date** | 10/24/2025 | 24/10/2025 | 2025/10/24 | | **Currency** | $1,234.56 | £1,234.56 | ¥1,235 | | **Number** | 1,234.56 | 1,234.56 | 1,234.56 | --- ## Translation Coverage Testing ```javascript test('all strings are translated', () => { const enKeys = Object.keys(translations.en); const frKeys = Object.keys(translations.fr); const esKeys = Object.keys(translations.es); // All locales have same keys expect(frKeys).toEqual(enKeys); expect(esKeys).toEqual(enKeys); }); test('no missing translation placeholders', async ({ page }) => { await page.goto('/?lang=fr'); const text = await page.textContent('body'); // Should not see placeholder keys expect(text).not.toContain('translation.missing'); expect(text).not.toMatch(/\{\{.*\}\}/); // {{key}} format }); ``` --- ## Date/Time/Currency Formats ```javascript test('date formats by locale', () => { const date = new Date('2025-10-24'); expect(formatDate(date, 'en-US')).toBe('10/24/2025'); expect(formatDate(date, 'en-GB')).toBe('24/10/2025'); expect(formatDate(date, 'ja-JP')).toBe('2025/10/24'); }); test('currency formats by locale', () => { const amount = 1234.56; expect(formatCurrency(amount, 'en-US', 'USD')).toBe('$1,234.56'); expect(formatCurrency(amount, 'de-DE', 'EUR')).toBe('1.234,56 €'); expect(formatCurrency(amount, 'ja-JP', 'JPY')).toBe('¥1,235'); }); ``` --- ## RTL (Right-to-Left) Testing ```javascript test('layout flips for RTL languages', async ({ page }) => { await page.goto('/?lang=ar'); // Arabic const dir = await page.locator('html').getAttribute('dir'); expect(dir).toBe('rtl'); // Navigation should be on right const nav = await page.locator('nav'); const styles = await nav.evaluate(el => window.getComputedStyle(el) ); expect(styles.direction).toBe('rtl'); }); test('icons/images appropriate for RTL', async ({ page }) => { await page.goto('/?lang=he'); // Hebrew // Back arrow should point right in RTL const backIcon = await page.locator('.back-icon'); expect(await backIcon.getAttribute('class')).toContain('rtl-flipped'); }); ``` --- ## Unicode Character Support ```javascript test('supports unicode characters', async ({ page }) => { // Japanese await page.fill('#name', '山田太郎'); await page.click('#submit'); const saved = await db.users.findOne({ /* ... */ }); expect(saved.name).toBe('山田太郎'); // Arabic await page.fill('#name', 'محمد'); // Emoji await page.fill('#bio', '👋🌍'); expect(saved.bio).toBe('👋🌍'); }); ``` --- ## Agent-Driven Localization Testing ```typescript // Comprehensive localization validation await Task("Localization Testing", { url: 'https://example.com', locales: ['en-US', 'fr-FR', 'de-DE', 'ja-JP', 'ar-SA'], checks: ['translations', 'formats', 'rtl', 'unicode'], detectHardcodedStrings: true }, "qe-test-generator"); // Returns: // { // locales: 5, // missingTranslations: 3, // formatIssues: 1, // rtlIssues: 0, // hardcodedStrings: ['button.submit', 'header.title'] // } ``` --- ## Agent Coordination Hints ### Memory Namespace ``` aqe/localization-testing/ ├── translations/* - Translation coverage ├── formats/* - Locale-specific formats ├── rtl-validation/* - RTL layout checks └── unicode/* - Character encoding tests ``` ### Fleet Coordination ```typescript const l10nFleet = await FleetManager.coordinate({ strategy: 'localization-testing', agents: [ 'qe-test-generator', // Generate l10n tests 'qe-test-executor', // Execute across locales 'qe-visual-tester' // RTL visual validation ], topology: 'parallel' }); ``` --- ## Related Skills - [accessibility-testing](../accessibility-testing/) - Language accessibility - [compatibility-testing](../compatibility-testing/) - Cross-platform i18n - [visual-testing-advanced](../visual-testing-advanced/) - RTL visual regression --- ## Remember **Don't hardcode. Externalize all user-facing strings.** Every string visible to users must come from translation files, not code. **Test with native speakers, not just translation files.** Machine translations and translation files can have context issues that only native speakers catch. **With Agents:** Agents validate translation coverage, detect hardcoded strings, test locale-specific formatting, and verify RTL layouts automatically across all supported languages.