test: Enhance localization handling in devices screen tests with a fake gettext delegate

Author: oldrev

client/test/core/services/scene_manager_impl_test.dart

@@ -7,6 +7,10 @@ import 'package:sembast/sembast_memory.dart';
 import '../../mocks/mocks.dart';
 
 void main() {
+  // some tests in this file access asset bundles via ServicesBinding; ensure
+  // the binding is initialized before any code runs.
+  TestWidgetsFlutterBinding.ensureInitialized();
+
   group('SceneManagerImpl', () {
     late SceneManagerImpl manager;
     late EventBus bus;

client/test/features/devices/devices_screen_test.dart

@@ -3,11 +3,27 @@ import 'package:borneo_app/features/devices/view_models/grouped_devices_view_mod
 import 'package:borneo_app/core/models/scene_entity.dart';
 import 'package:borneo_app/core/models/events.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter_gettext/flutter_gettext/gettext_localizations.dart';
 import '../../mocks/mocks.dart';
 import 'package:event_bus/event_bus.dart';
 import 'package:flutter_test/flutter_test.dart' hide EventDispatcher;
 import 'package:provider/provider.dart';
 
+// A simple delegate that always returns [FakeGettext] so widgets
+// calling `GettextLocalizations.of(context)` don't crash.
+class _FakeGettextDelegate extends LocalizationsDelegate<GettextLocalizations> {
+  const _FakeGettextDelegate();
+
+  @override
+  bool isSupported(Locale locale) => true;
+
+  @override
+  Future<GettextLocalizations> load(Locale locale) async => FakeGettext();
+
+  @override
+  bool shouldReload(covariant LocalizationsDelegate<GettextLocalizations> old) => false;
+}
+
 void main() {
   testWidgets('AppBar title updates when scene name changes', (WidgetTester tester) async {
     final bus = EventBus();
@@ -27,18 +43,22 @@ void main() {
 
     await tester.pumpWidget(
       MaterialApp(
+        localizationsDelegates: const [_FakeGettextDelegate()],
+        supportedLocales: const [Locale('en', 'US')],
         home: ChangeNotifierProvider<GroupedDevicesViewModel>.value(value: vm, child: DevicesScreen()),
       ),
     );
+    // give the framework a chance to lay out slivers, etc.
+    await tester.pumpAndSettle();
 
-    // initial title should reflect "Initial"
-    expect(find.textContaining('Initial'), findsOneWidget);
+    // initial title should reflect the scene name via the translation string
+    expect(find.textContaining('Devices in Initial'), findsOneWidget);
 
     // modify scene name and fire event
     sceneMgr.currentScene = scene.copyWith(name: 'Updated');
     bus.fire(SceneUpdatedEvent(sceneMgr.currentScene));
-    await tester.pump();
+    await tester.pumpAndSettle();
 
-    expect(find.textContaining('Updated'), findsOneWidget);
+    expect(find.textContaining('Devices in Updated'), findsOneWidget);
   });
 }

client/test/mocks/gettext.dart

@@ -10,5 +10,17 @@ class FakeGettext implements GettextLocalizations {
     String msgctxt = '',
     Map<String, Object>? nArgs,
     List<Object>? pArgs,
-  }) => key;
+  }) {
+    if (nArgs != null && nArgs.isNotEmpty) {
+      nArgs.forEach((name, value) {
+        key = key.replaceAll('{$name}', value.toString());
+      });
+    }
+    if (pArgs != null && pArgs.isNotEmpty) {
+      for (var i = 0; i < pArgs.length; i++) {
+        key = key.replaceAll('{$i}', pArgs[i].toString());
+      }
+    }
+    return key;
+  }
 }