nav: Add a button for MentionsNarrow.

Signed-off-by: Zixuan James Li <[email protected]>

Author: PIG208

lib/widgets/app.dart

@@ -276,6 +276,12 @@ class HomePage extends StatelessWidget {
                 narrow: const CombinedFeedNarrow())),
             child: Text(zulipLocalizations.combinedFeedPageTitle)),
           const SizedBox(height: 16),
+          ElevatedButton(
+            onPressed: () => Navigator.push(context,
+              MessageListPage.buildRoute(context: context,
+                narrow: const MentionsNarrow())),
+            child: Text(zulipLocalizations.mentionsPageTitle)),
+          const SizedBox(height: 16),
           ElevatedButton(
             onPressed: () => Navigator.push(context,
               InboxPage.buildRoute(context: context)),

test/widgets/message_list_test.dart

@@ -950,29 +950,6 @@ void main() {
         check(store.unreads).oldUnreadsMissing.isTrue();
       });
 
-      testWidgets('MentionsNarrow on legacy server', (WidgetTester tester) async {
-        await setupMessageListPage(tester,
-          narrow: const MentionsNarrow(),
-          messages: [eg.streamMessage(flags: [MessageFlag.mentioned])],
-          unreadMsgs: eg.unreadMsgs(mentions: [message.id]),
-        );
-        check(isMarkAsReadButtonVisible(tester)).isTrue();
-
-        connection.zulipFeatureLevel = 154;
-        connection.prepare(json:
-          UpdateMessageFlagsResult(messages: [message.id]).toJson());
-        await tester.tap(find.byType(MarkAsReadWidget));
-        check(connection.lastRequest).isA<http.Request>()
-          ..method.equals('POST')
-          ..url.path.equals('/api/v1/messages/flags')
-          ..bodyFields.deepEquals({
-              'messages': jsonEncode([message.id]),
-              'op': 'add',
-              'flag': 'read',
-            });
-          await tester.pumpAndSettle();
-      });
-
       testWidgets('StreamNarrow on legacy server', (WidgetTester tester) async {
         final narrow = StreamNarrow(message.streamId);
         await setupMessageListPage(tester,
@@ -1039,6 +1016,29 @@ void main() {
         await tester.pumpAndSettle(); // process pending timers
       });
 
+      testWidgets('MentionsNarrow on legacy server', (WidgetTester tester) async {
+        await setupMessageListPage(tester,
+          narrow: const MentionsNarrow(),
+          messages: [eg.streamMessage(flags: [MessageFlag.mentioned])],
+          unreadMsgs: eg.unreadMsgs(mentions: [message.id]),
+        );
+        check(isMarkAsReadButtonVisible(tester)).isTrue();
+
+        connection.zulipFeatureLevel = 154;
+        connection.prepare(json:
+          UpdateMessageFlagsResult(messages: [message.id]).toJson());
+        await tester.tap(find.byType(MarkAsReadWidget));
+        check(connection.lastRequest).isA<http.Request>()
+          ..method.equals('POST')
+          ..url.path.equals('/api/v1/messages/flags')
+          ..bodyFields.deepEquals({
+              'messages': jsonEncode([message.id]),
+              'op': 'add',
+              'flag': 'read',
+            });
+          await tester.pumpAndSettle();
+      });
+
       testWidgets('catch-all api errors', (WidgetTester tester) async {
         final zulipLocalizations = GlobalLocalizations.zulipLocalizations;
         const narrow = CombinedFeedNarrow();