fix(ui_localizations): loading Traditional Chinese

packages/firebase_ui_localizations/lib/src/all_languages.dart

@@ -1,52 +1,121 @@
 // Copyright 2023, the Chromium project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-import "./default_localizations.dart";
+import 'dart:ui';
 
+import "./default_localizations.dart";
+import 'lang/ar.dart';
+import 'lang/de.dart';
+import 'lang/en.dart';
 import 'lang/es.dart';
 import 'lang/es_419.dart';
-import 'lang/ko.dart';
+import 'lang/fr.dart';
+import 'lang/he.dart';
+import 'lang/hi.dart';
 import 'lang/hu.dart';
 import 'lang/id.dart';
-import 'lang/pt.dart';
-import 'lang/he.dart';
-import 'lang/de.dart';
 import 'lang/it.dart';
-import 'lang/zh.dart';
-import 'lang/zh_tw.dart';
-import 'lang/uk.dart';
-import 'lang/th.dart';
-import 'lang/ar.dart';
-import 'lang/tr.dart';
+import 'lang/ja.dart';
+import 'lang/ko.dart';
 import 'lang/nl.dart';
 import 'lang/pl.dart';
-import 'lang/en.dart';
-import 'lang/ja.dart';
-import 'lang/hi.dart';
+import 'lang/pt.dart';
 import 'lang/ru.dart';
-import 'lang/fr.dart';
+import 'lang/th.dart';
+import 'lang/tr.dart';
+import 'lang/uk.dart';
+import 'lang/zh.dart';
+import 'lang/zh_tw.dart';
 
-final localizations = <String, FirebaseUILocalizationLabels>{
-  'es': const EsLocalizations(),
-  'es_419': const Es419Localizations(),
-  'ko': const KoLocalizations(),
-  'hu': const HuLocalizations(),
-  'id': const IdLocalizations(),
-  'pt': const PtLocalizations(),
-  'he': const HeLocalizations(),
-  'de': const DeLocalizations(),
-  'it': const ItLocalizations(),
-  'zh': const ZhLocalizations(),
-  'zh_tw': const ZhTWLocalizations(),
-  'uk': const UkLocalizations(),
-  'th': const ThLocalizations(),
-  'ar': const ArLocalizations(),
-  'tr': const TrLocalizations(),
-  'nl': const NlLocalizations(),
-  'pl': const PlLocalizations(),
-  'en': const EnLocalizations(),
-  'ja': const JaLocalizations(),
-  'hi': const HiLocalizations(),
-  'ru': const RuLocalizations(),
-  'fr': const FrLocalizations(),
+final Set<String> kSupportedLanguages = {
+  'ar', // Arabic
+  'de', // German
+  'en', // English
+  'es', // Spanish Castilian
+  'fr', // French
+  'he', // Hebrew
+  'hi', // Hindi
+  'hu', // Hungarian
+  'id', // Indonesian
+  'it', // Italian
+  'ja', // Japanese
+  'ko', // Korean
+  'nl', // Dutch Flemish
+  'pl', // Polish
+  'pt', // Portuguese
+  'ru', // Russian
+  'th', // Thai
+  'tr', // Turkish
+  'uk', // Ukrainian
+  'zh', // Chinese
 };
+
+FirebaseUILocalizationLabels getFirebaseUITranslation(
+  Locale useLocale, [
+  Locale? defaultLocale,
+]) {
+  final Locale locale;
+  if (kSupportedLanguages.contains(useLocale.languageCode)) {
+    locale = useLocale;
+  } else {
+    locale = defaultLocale ?? useLocale;
+  }
+
+  switch (locale.languageCode) {
+    case 'ar':
+      return const ArLocalizations();
+    case 'de':
+      return const DeLocalizations();
+    case 'en':
+      return const EnLocalizations();
+    case 'es':
+      switch (locale.countryCode) {
+        case '419':
+          return const Es419Localizations();
+      }
+      return const EsLocalizations();
+    case 'fr':
+      return const FrLocalizations();
+    case 'he':
+      return const HeLocalizations();
+    case 'hi':
+      return const HiLocalizations();
+    case 'hu':
+      return const HuLocalizations();
+    case 'id':
+      return const IdLocalizations();
+    case 'it':
+      return const ItLocalizations();
+    case 'ja':
+      return const JaLocalizations();
+    case 'ko':
+      return const KoLocalizations();
+    case 'nl':
+      return const NlLocalizations();
+    case 'pl':
+      return const PlLocalizations();
+    case 'pt':
+      return const PtLocalizations();
+    case 'ru':
+      return const RuLocalizations();
+    case 'th':
+      return const ThLocalizations();
+    case 'tr':
+      return const TrLocalizations();
+    case 'uk':
+      return const UkLocalizations();
+    case 'zh':
+      switch (locale.scriptCode) {
+        case 'Hant':
+          return const ZhTWLocalizations();
+      }
+      switch (locale.countryCode) {
+        case 'HK':
+        case 'TW':
+          return const ZhTWLocalizations();
+      }
+      return const ZhLocalizations();
+  }
+
+  throw ('getTranslationLabels() called for unsupported locale "$locale"');
+}

packages/firebase_ui_localizations/lib/src/l10n.dart

@@ -36,8 +36,8 @@ class FirebaseUILocalizations<T extends FirebaseUILocalizationLabels> {
       return l;
     }
 
-    final defaultLocalizations = localizations[kDefaultLocale.languageCode]!;
-    return FirebaseUILocalizations(kDefaultLocale, defaultLocalizations);
+    final defaultTranslation = getFirebaseUITranslation(kDefaultLocale);
+    return FirebaseUILocalizations(kDefaultLocale, defaultTranslation);
   }
 
   /// Returns localization labels.
@@ -74,32 +74,20 @@ class FirebaseUILocalizationDelegate<T extends FirebaseUILocalizationLabels>
   ]);
 
   @override
-  bool isSupported(Locale locale) {
-    return _forceSupportAllLocales ||
-        localizations.keys.contains(locale.languageCode);
-  }
+  bool isSupported(Locale locale) =>
+      _forceSupportAllLocales ||
+      kSupportedLanguages.contains(locale.languageCode);
 
   @override
   Future<FirebaseUILocalizations> load(Locale locale) {
-    late FirebaseUILocalizationLabels labels;
-
-    final key = locale.languageCode;
-    final fullKey = '${key}_${locale.countryCode.toString()}';
-
-    if (localizations.containsKey(fullKey)) {
-      labels = localizations[fullKey]!;
-    } else if (localizations.containsKey(key)) {
-      labels = localizations[key]!;
-    } else {
-      labels = localizations[kDefaultLocale.languageCode]!;
-    }
+    final translation = getFirebaseUITranslation(locale, kDefaultLocale);
 
-    final l = FirebaseUILocalizations(
+    final localizations = FirebaseUILocalizations(
       locale,
-      overrides ?? labels,
+      overrides ?? translation,
     );
 
-    return SynchronousFuture<FirebaseUILocalizations>(l);
+    return SynchronousFuture<FirebaseUILocalizations>(localizations);
   }
 
   @override

packages/firebase_ui_localizations/test/firebase_ui_localizations_test.dart

@@ -0,0 +1,171 @@
+// Copyright 2022, the Chromium project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:firebase_ui_localizations/firebase_ui_localizations.dart';
+import 'package:firebase_ui_localizations/src/lang/zh_tw.dart';
+import 'package:flutter/material.dart';
+import 'package:flutter_localizations/flutter_localizations.dart';
+import 'package:flutter_test/flutter_test.dart';
+
+const localeZh = Locale('zh');
+const localeTW = Locale('zh', 'TW');
+
+Future<void> main() async {
+  late FirebaseUILocalizationDelegate delegate;
+
+  group(
+    'FirebaseUILocalization loads the appropriate Chinese translation',
+    () {
+      localizedText(BuildContext context) => FirebaseUILocalizations.labelsOf(context).signInWithPhoneButtonText;
+
+      setUp(() async {
+        delegate = const FirebaseUILocalizationDelegate();
+      });
+
+      test(
+        'Loads the correct translation with the language tag "${localeZh.toLanguageTag()}"',
+        () async {
+          final localizations = await delegate.load(localeZh);
+          expect(localizations.labels.signInWithPhoneButtonText, '使用电话号码登录');
+        },
+      );
+
+      testWidgets(
+        'UI test for the "${localeZh.toLanguageTag()}" translation',
+        (tester) async {
+          await tester.pumpWidget(
+            TestMaterialApp(
+              locale: localeZh,
+              localizedText: localizedText,
+            ),
+          );
+          expect(find.text('使用电话号码登录'), findsOneWidget);
+        },
+      );
+
+      test(
+        'Loads the correct translation with the language tag "${localeTW.toLanguageTag()}"',
+        () async {
+          final localizations = await delegate.load(localeTW);
+          expect(localizations.labels.signInWithPhoneButtonText, '使用電話號碼登入');
+        },
+      );
+
+      testWidgets(
+        'UI test for the "${localeTW.toLanguageTag()}" translation',
+        (tester) async {
+          await tester.pumpWidget(
+            TestMaterialApp(
+              locale: localeTW,
+              localizedText: localizedText,
+            ),
+          );
+          expect(find.text('使用電話號碼登入'), findsOneWidget);
+        },
+      );
+    },
+  );
+
+  group(
+    'Localization override',
+    () {
+      localizedText(BuildContext context) => FirebaseUILocalizations.labelsOf(context).verifyEmailTitle;
+
+      test(
+        'Overrides the DefaultLocalizations',
+        () async {
+          final localizations = await const FirebaseUILocalizationDelegate(
+            DefaultLocalizationsOverrides(),
+          ).load(localeTW);
+          expect(localizations.labels.verifyEmailTitle, 'Overwritten');
+        },
+      );
+
+      testWidgets(
+        'UI test for the default translation override',
+        (tester) async {
+          await tester.pumpWidget(
+            TestMaterialApp(
+              locale: localeZh,
+              localizationsOverride: const FirebaseUILocalizationDelegate(
+                DefaultLocalizationsOverrides(),
+              ),
+              localizedText: localizedText,
+            ),
+          );
+          expect(find.text('Overwritten'), findsOneWidget);
+        },
+      );
+
+      test(
+        'Overrides the DefaultLocalizations',
+        () async {
+          final localizations = await const FirebaseUILocalizationDelegate(
+            ZhTWLocalizationsOverrides(),
+          ).load(localeTW);
+          expect(localizations.labels.verifyEmailTitle, '覆寫標題');
+        },
+      );
+
+      testWidgets(
+        'UI test for the "${localeTW.toLanguageTag()}" translation override',
+        (tester) async {
+          await tester.pumpWidget(
+            TestMaterialApp(
+              locale: localeTW,
+              localizationsOverride: const FirebaseUILocalizationDelegate(
+                ZhTWLocalizationsOverrides(),
+              ),
+              localizedText: localizedText,
+            ),
+          );
+          expect(find.text('覆寫標題'), findsOneWidget);
+        },
+      );
+    },
+  );
+}
+
+class DefaultLocalizationsOverrides extends DefaultLocalizations {
+  const DefaultLocalizationsOverrides();
+
+  @override
+  String get verifyEmailTitle => 'Overwritten';
+}
+
+class ZhTWLocalizationsOverrides extends ZhTWLocalizations {
+  const ZhTWLocalizationsOverrides();
+
+  @override
+  String get verifyEmailTitle => '覆寫標題';
+}
+
+class TestMaterialApp extends StatelessWidget {
+  final Locale locale;
+  final LocalizationsDelegate? localizationsOverride;
+  final String Function(BuildContext context) localizedText;
+
+  const TestMaterialApp({
+    super.key,
+    required this.locale,
+    this.localizationsOverride,
+    required this.localizedText,
+  });
+
+  @override
+  Widget build(BuildContext context) => MaterialApp(
+        supportedLocales: const [localeZh, localeTW],
+        locale: locale,
+        localizationsDelegates: [
+          GlobalMaterialLocalizations.delegate,
+          GlobalCupertinoLocalizations.delegate,
+          localizationsOverride == null ? FirebaseUILocalizations.delegate : localizationsOverride!,
+        ],
+        home: Builder(
+          builder: (context) => Text(
+            localizedText.call(context),
+          ),
+        ),
+      );
+}