inbox: Show topic visibility marker for topic items

Signed-off-by: Zixuan James Li <zixuan@zulip.com>

Author: PIG208

lib/widgets/inbox.dart

@@ -514,6 +514,8 @@ class _TopicItem extends StatelessWidget {
     final subscription = store.subscriptions[streamId]!;
 
     final designVariables = DesignVariables.of(context);
+    final visibilityIcon = iconDataForTopicVisibilityPolicy(
+      store.topicVisibilityPolicy(streamId, topic));
 
     return Material(
       color: designVariables.background, // TODO(design) check if this is the right variable
@@ -540,6 +542,8 @@ class _TopicItem extends StatelessWidget {
                 topic))),
             const SizedBox(width: 12),
             if (hasMention) const _IconMarker(icon: ZulipIcons.at_sign),
+            // TODO(design) copies the "@" marker color; is there a better color?
+            if (visibilityIcon != null) _IconMarker(icon: visibilityIcon),
             Padding(padding: const EdgeInsetsDirectional.only(end: 16),
               child: UnreadCountBadge(
                 backgroundColor: colorSwatchFor(context, subscription),

test/widgets/inbox_test.dart

@@ -305,6 +305,53 @@ void main() {
       });
     });
 
+    group('topic visibility', () {
+      final channel = eg.stream();
+      const topic = 'topic';
+      final message = eg.streamMessage(stream: channel, topic: topic);
+
+      testWidgets('followed', (tester) async {
+        await setupPage(tester,
+          streams: [channel],
+          subscriptions: [eg.subscription(channel)],
+          unreadMessages: [message]);
+        await store.addUserTopic(channel, topic, UserTopicVisibilityPolicy.followed);
+        await tester.pump();
+        check(hasIcon(tester,
+          parent: findRowByLabel(tester, topic),
+          icon: ZulipIcons.follow)).isTrue();
+      });
+
+      testWidgets('followed and mentioned', (tester) async {
+        await setupPage(tester,
+          streams: [channel],
+          subscriptions: [eg.subscription(channel)],
+          unreadMessages: [eg.streamMessage(stream: channel, topic: topic,
+            flags: [MessageFlag.mentioned])]);
+        await store.addUserTopic(channel, topic, UserTopicVisibilityPolicy.followed);
+        await tester.pump();
+        check(hasIcon(tester,
+          parent: findRowByLabel(tester, topic),
+          icon: ZulipIcons.follow)).isTrue();
+        check(hasIcon(tester,
+          parent: findRowByLabel(tester, topic),
+          icon: ZulipIcons.at_sign)).isTrue();
+      });
+
+      testWidgets('unmuted', (tester) async {
+        await setupPage(tester,
+          users: [eg.selfUser, eg.otherUser],
+          streams: [channel],
+          subscriptions: [eg.subscription(channel, isMuted: true)],
+          unreadMessages: [message]);
+        await store.addUserTopic(channel, topic, UserTopicVisibilityPolicy.unmuted);
+        await tester.pump();
+        check(hasIcon(tester,
+          parent: findRowByLabel(tester, topic),
+          icon: ZulipIcons.unmute)).isTrue();
+      });
+    });
+
     group('collapsing', () {
       Icon findHeaderCollapseIcon(WidgetTester tester, Widget headerRow) {
         return tester.widget(