test: add browser-based unit tests for helpers, i18n, router

tests/i18n.test.js

@@ -0,0 +1,91 @@
+/**
+ * Tests for js/i18n.js
+ */
+
+import { test, describe, assertEquals, assertTrue } from './test-runner.js'
+import { i18n, t } from '../js/i18n.js'
+
+describe('i18n.getNestedValue', () => {
+    const obj = {
+        home: {
+            title: 'Welcome',
+            nested: {
+                deep: 'Deep Value'
+            }
+        },
+        simple: 'Simple Value'
+    }
+
+    test('gets top-level value', () => {
+        assertEquals(i18n.getNestedValue(obj, 'simple'), 'Simple Value')
+    })
+
+    test('gets nested value', () => {
+        assertEquals(i18n.getNestedValue(obj, 'home.title'), 'Welcome')
+    })
+
+    test('gets deeply nested value', () => {
+        assertEquals(i18n.getNestedValue(obj, 'home.nested.deep'), 'Deep Value')
+    })
+
+    test('returns undefined for missing key', () => {
+        assertEquals(i18n.getNestedValue(obj, 'missing'), undefined)
+    })
+
+    test('returns undefined for missing nested key', () => {
+        assertEquals(i18n.getNestedValue(obj, 'home.missing'), undefined)
+    })
+})
+
+describe('i18n.t (translation)', () => {
+    // Note: These tests require translations to be loaded
+    // They test the parameter interpolation logic
+
+    test('returns key if translation missing', () => {
+        const result = i18n.t('this.key.does.not.exist')
+        assertEquals(result, 'this.key.does.not.exist')
+    })
+})
+
+describe('i18n.getLocale', () => {
+    test('returns current locale', () => {
+        const locale = i18n.getLocale()
+        assertTrue(['de', 'en', 'fr'].includes(locale))
+    })
+})
+
+describe('i18n.getSupportedLocales', () => {
+    test('returns array of supported locales', () => {
+        const locales = i18n.getSupportedLocales()
+        assertTrue(Array.isArray(locales))
+        assertTrue(locales.includes('de'))
+        assertTrue(locales.includes('en'))
+        assertTrue(locales.includes('fr'))
+    })
+})
+
+describe('i18n.getLocaleDisplayName', () => {
+    test('returns Deutsch for de', () => {
+        assertEquals(i18n.getLocaleDisplayName('de'), 'Deutsch')
+    })
+
+    test('returns English for en', () => {
+        assertEquals(i18n.getLocaleDisplayName('en'), 'English')
+    })
+
+    test('returns Français for fr', () => {
+        assertEquals(i18n.getLocaleDisplayName('fr'), 'Français')
+    })
+
+    test('returns locale code for unknown locale', () => {
+        assertEquals(i18n.getLocaleDisplayName('xx'), 'xx')
+    })
+})
+
+describe('i18n.subscribe', () => {
+    test('returns unsubscribe function', () => {
+        const unsubscribe = i18n.subscribe(() => {})
+        assertEquals(typeof unsubscribe, 'function')
+        unsubscribe()
+    })
+})