feat: import Chinese-localized Buzz source snapshot

Signed-off-by: cls_宁波本机 <908705107@qq.com>

mobile/test/features/channels/send_message_provider_test.dart

@@ -0,0 +1,121 @@
+import 'dart:async';
+
+import 'package:flutter_test/flutter_test.dart';
+import 'package:hooks_riverpod/hooks_riverpod.dart';
+import 'package:nostr/nostr.dart' as nostr;
+import 'package:buzz/features/channels/send_message_provider.dart';
+import 'package:buzz/shared/relay/relay.dart';
+
+void main() {
+  test(
+    'adds the signed message locally before relay acknowledgement',
+    () async {
+      final session = _PendingPublishRelaySession();
+      final localMessages = <NostrEvent>[];
+      final removedIds = <String>[];
+      final completedIds = <String>[];
+      final send = SendMessage(
+        signedEventRelay: SignedEventRelay(
+          session: session,
+          nsec: nostr.Keys.generate().nsec,
+        ),
+        fetchMembers: (_) async => const [],
+        readUserCache: () => const {},
+        addLocalMessage: (_, event) => localMessages.add(event),
+        completeLocalMessage: (_, eventId) => completedIds.add(eventId),
+        removeLocalMessage: (_, eventId) => removedIds.add(eventId),
+      );
+
+      final result = send(channelId: _channelId, content: 'hello');
+      await session.published;
+
+      expect(localMessages, hasLength(1));
+      expect(localMessages.single.id, session.event.id);
+      expect(localMessages.single.content, 'hello');
+      expect(localMessages.single.channelId, _channelId);
+      expect(removedIds, isEmpty);
+
+      session.accept();
+      await result;
+      expect(completedIds, [localMessages.single.id]);
+      expect(removedIds, isEmpty);
+    },
+  );
+
+  test('rolls back the signed local message when publish fails', () async {
+    final session = _PendingPublishRelaySession();
+    final localMessages = <NostrEvent>[];
+    final completedIds = <String>[];
+    final removedIds = <String>[];
+    final send = SendMessage(
+      signedEventRelay: SignedEventRelay(
+        session: session,
+        nsec: nostr.Keys.generate().nsec,
+      ),
+      fetchMembers: (_) async => const [],
+      readUserCache: () => const {},
+      addLocalMessage: (_, event) => localMessages.add(event),
+      completeLocalMessage: (_, eventId) => completedIds.add(eventId),
+      removeLocalMessage: (_, eventId) => removedIds.add(eventId),
+    );
+
+    final result = send(channelId: _channelId, content: 'hello');
+    await session.published;
+    session.reject();
+
+    await expectLater(result, throwsException);
+    expect(completedIds, isEmpty);
+    expect(removedIds, [localMessages.single.id]);
+  });
+
+  test('cancels delivery after the active community changes', () async {
+    final container = ProviderContainer();
+    addTearDown(container.dispose);
+    container
+        .read(relayConfigProvider.notifier)
+        .update(baseUrl: 'https://first.example');
+    final send = container.read(sendMessageProvider);
+
+    container
+        .read(relayConfigProvider.notifier)
+        .update(baseUrl: 'https://second.example');
+
+    await expectLater(
+      send(channelId: _channelId, content: 'old community draft'),
+      throwsA(
+        isA<StateError>().having(
+          (error) => error.message,
+          'message',
+          contains('active community changed'),
+        ),
+      ),
+    );
+  });
+}
+
+const _channelId = '11111111-1111-4111-8111-111111111111';
+
+class _PendingPublishRelaySession extends RelaySessionNotifier {
+  final Completer<NostrEvent> _result = Completer<NostrEvent>();
+  final Completer<void> _published = Completer<void>();
+  late NostrEvent event;
+
+  Future<void> get published => _published.future;
+
+  @override
+  SessionState build() => const SessionState(status: SessionStatus.connected);
+
+  @override
+  Future<NostrEvent> publish(
+    NostrEvent event, {
+    Duration timeout = const Duration(seconds: 8),
+  }) {
+    this.event = event;
+    _published.complete();
+    return _result.future;
+  }
+
+  void accept() => _result.complete(event);
+
+  void reject() => _result.completeError(Exception('relay rejected event'));
+}