i18n: use zh-Hant for Chinese (Traditional)

src/i18n/firms-live-zh.test.mjs

@@ -36,7 +36,7 @@ for (const [age, zh, en, tw] of cases) {
       assert.equal(methods.getStats().loadingLabel, `LIVE · updated ${en}`);
       setLocale('zh-CN');
       assert.equal(methods.getStats().loadingLabel, `实时 · 更新于 ${zh}`);
-      setLocale('zh-TW');
+      setLocale('zh-Hant');
       assert.equal(methods.getStats().loadingLabel, `即時 · 更新於 ${tw}`);
     } finally {
       setLocale(previousLocale);

src/i18n/i18n.test.mjs

@@ -39,12 +39,14 @@ test('normalizeLocale folds regional variants and rejects unshipped tags', () =>
   assert.equal(normalizeLocale('zh'), 'zh-CN');
   assert.equal(normalizeLocale('zh-CN'), 'zh-CN');
   assert.equal(normalizeLocale('zh-Hans-SG'), 'zh-CN');
-  assert.equal(normalizeLocale('zh-TW'), 'zh-TW');
-  assert.equal(normalizeLocale('zh-Hant-HK'), 'zh-TW');
+  assert.equal(normalizeLocale('zh-Hant'), 'zh-Hant');
+  assert.equal(normalizeLocale(' ZH_hant '), 'zh-Hant');
+  assert.equal(normalizeLocale('zh-TW'), 'zh-Hant');
+  assert.equal(normalizeLocale('zh-Hant-HK'), 'zh-Hant');
   assert.equal(normalizeLocale('zh-Hans-TW'), 'zh-CN');
-  assert.equal(normalizeLocale('zh-Hant-CN'), 'zh-TW');
-  assert.equal(normalizeLocale('zh_HK'), 'zh-TW');
-  assert.equal(normalizeLocale('zh-MO'), 'zh-TW');
+  assert.equal(normalizeLocale('zh-Hant-CN'), 'zh-Hant');
+  assert.equal(normalizeLocale('zh_HK'), 'zh-Hant');
+  assert.equal(normalizeLocale('zh-MO'), 'zh-Hant');
   assert.equal(normalizeLocale(undefined), null);
 });
 

src/i18n/index.js

@@ -19,9 +19,9 @@ import {
 import es from './locales/es.json' with { type: 'json' };
 import ru from './locales/ru.json' with { type: 'json' };
 import zhCN from './locales/zh-CN.json' with { type: 'json' };
-import zhTW from './locales/zh-TW.json' with { type: 'json' };
+import zhHant from './locales/zh-Hant.json' with { type: 'json' };
 
-const CATALOGS = Object.freeze({ es, ru, 'zh-CN': zhCN, 'zh-TW': zhTW });
+const CATALOGS = Object.freeze({ es, ru, 'zh-CN': zhCN, 'zh-Hant': zhHant });
 
 let currentLocale = DEFAULT_LOCALE;
 

src/i18n/locale.js

@@ -8,15 +8,15 @@ export const LOCALE_STORAGE_KEY = 'gev:locale:v1';
 export const DEFAULT_LOCALE = 'en';
 
 /** Shipped locales; order does not matter. Adding one: docs/TRANSLATORS.md. */
-export const LOCALES = Object.freeze(['en', 'es', 'ru', 'zh-CN', 'zh-TW']);
+export const LOCALES = Object.freeze(['en', 'es', 'ru', 'zh-CN', 'zh-Hant']);
 
 /** Each locale named in its own language, for the selector. */
 export const LOCALE_NAMES = Object.freeze({
   en: 'English',
   es: 'Español',
   ru: 'Русский',
-  'zh-CN': '简体中文',
-  'zh-TW': '繁體中文',
+  'zh-CN': '中文（简体）',
+  'zh-Hant': '中文（繁體）',
 });
 
 /** Right-to-left locales. */
@@ -24,7 +24,8 @@ const RTL_LOCALES = Object.freeze([]);
 
 /**
  * Map any language tag to a shipped locale: 'ru-RU' and 'RU' → 'ru',
- * 'zh', 'zh-CN' and 'zh-Hans-SG' → 'zh-CN'.
+ * 'zh', 'zh-CN' and 'zh-Hans-SG' → 'zh-CN';
+ * 'zh-Hant', 'zh-TW', 'zh-HK' and 'zh-MO' → 'zh-Hant'.
  * @returns {string|null}
  */
 export function normalizeLocale(candidate) {
@@ -33,7 +34,7 @@ export function normalizeLocale(candidate) {
   if (primary === 'zh') {
     if (rest.includes('hans')) return 'zh-CN';
     return rest.some((part) => ['hant', 'tw', 'hk', 'mo'].includes(part))
-      ? 'zh-TW'
+      ? 'zh-Hant'
       : 'zh-CN';
   }
   return LOCALES.includes(primary) ? primary : null;

src/i18n/same-as-english.json

@@ -193,7 +193,7 @@
     "ΔN",
     "▲ {frp} MW"
   ],
-  "zh-TW": [
+  "zh-Hant": [
     "1090 MHz",
     "978 MHz UAT",
     "AIS: --",

src/i18n/zh-Hant-display.test.mjs

@@ -1,7 +1,12 @@
 import test from 'node:test';
 import assert from 'node:assert/strict';
 import { setLocale, t, tn, getLocale } from './index.js';
-import { resolveLocale, LOCALE_STORAGE_KEY } from './locale.js';
+import {
+  resolveLocale,
+  LOCALE_STORAGE_KEY,
+  writeStoredLocale,
+  applyDocumentLanguage,
+} from './locale.js';
 import { hudQuantity, LOCALIZED_LOCALITY } from '../hudLocalityFormat.js';
 import { formatCockpitDistance } from '../ui/cockpitPresentation.js';
 import { READOUT_WORDS } from '../layers/recentImagery/display.js';
@@ -14,7 +19,7 @@ test('Traditional Chinese resolves from URL, saved preference and browser langua
       storage: { getItem: () => 'en' },
       languages: ['en'],
     }),
-    'zh-TW',
+    'zh-Hant',
   );
   assert.equal(
     resolveLocale({
@@ -24,7 +29,7 @@ test('Traditional Chinese resolves from URL, saved preference and browser langua
       },
       languages: ['en'],
     }),
-    'zh-TW',
+    'zh-Hant',
   );
   assert.equal(
     resolveLocale({
@@ -32,14 +37,29 @@ test('Traditional Chinese resolves from URL, saved preference and browser langua
       storage: { getItem: () => null },
       languages: ['zh-Hant', 'en'],
     }),
-    'zh-TW',
+    'zh-Hant',
   );
 });
 
+test('Traditional Chinese persists and exposes the script locale for legacy choices', () => {
+  const stored = new Map();
+  assert.equal(
+    writeStoredLocale('zh-TW', {
+      setItem: (key, value) => stored.set(key, value),
+    }),
+    true,
+  );
+  assert.equal(stored.get(LOCALE_STORAGE_KEY), 'zh-Hant');
+  const doc = { documentElement: {} };
+  assert.equal(applyDocumentLanguage(doc, 'zh-TW'), true);
+  assert.equal(doc.documentElement.lang, 'zh-Hant');
+  assert.equal(doc.documentElement.dir, 'ltr');
+});
+
 test('Traditional Chinese readouts preserve unit case, coordinates and natural relative dates', () => {
   const previous = getLocale();
   try {
-    setLocale('zh-TW');
+    setLocale('zh-Hant');
     assert.equal(hudQuantity(2069, 'km', 1), '2069.0 km');
     assert.equal(formatCockpitDistance(14000), '14\u00a0km');
     assert.equal(