narrow [nfc]: Make containsMessage support MessageBase

This is NFC because we don't have non-testing subclasses of
MessageBase.

Author: PIG208

lib/model/narrow.dart

@@ -19,7 +19,7 @@ sealed class Narrow {
   /// This does not necessarily mean the message list would show this message
   /// when navigated to this narrow; in particular it does not address the
   /// question of whether the stream or topic, or the sending user, is muted.
-  bool containsMessage(Message message);
+  bool containsMessage(MessageBase message);
 
   /// This narrow, expressed as an [ApiNarrow].
   ApiNarrow apiEncode();
@@ -47,7 +47,7 @@ class CombinedFeedNarrow extends Narrow {
   const CombinedFeedNarrow();
 
   @override
-  bool containsMessage(Message message) {
+  bool containsMessage(MessageBase message) {
     return true;
   }
 
@@ -71,8 +71,9 @@ class ChannelNarrow extends Narrow {
   final int streamId;
 
   @override
-  bool containsMessage(Message message) {
-    return message is StreamMessage && message.streamId == streamId;
+  bool containsMessage(MessageBase message) {
+    final conversation = message.conversation;
+    return conversation is StreamConversation && conversation.streamId == streamId;
   }
 
   @override
@@ -105,9 +106,10 @@ class TopicNarrow extends Narrow implements SendableNarrow {
   TopicNarrow sansWith() => TopicNarrow(streamId, topic);
 
   @override
-  bool containsMessage(Message message) {
-    return (message is StreamMessage
-      && message.streamId == streamId && message.topic == topic);
+  bool containsMessage(MessageBase message) {
+    final conversation = message.conversation;
+    return conversation is StreamConversation
+      && conversation.streamId == streamId && conversation.topic == topic;
   }
 
   @override
@@ -263,11 +265,12 @@ class DmNarrow extends Narrow implements SendableNarrow {
   late final String _key = otherRecipientIds.join(',');
 
   @override
-  bool containsMessage(Message message) {
-    if (message is! DmMessage) return false;
-    if (message.allRecipientIds.length != allRecipientIds.length) return false;
+  bool containsMessage(MessageBase message) {
+    final conversation = message.conversation;
+    if (conversation is! DmConversation) return false;
+    if (conversation.allRecipientIds.length != allRecipientIds.length) return false;
     int i = 0;
-    for (final userId in message.allRecipientIds) {
+    for (final userId in conversation.allRecipientIds) {
       if (userId != allRecipientIds[i]) return false;
       i++;
     }
@@ -307,7 +310,8 @@ class MentionsNarrow extends Narrow {
   const MentionsNarrow();
 
   @override
-  bool containsMessage(Message message) {
+  bool containsMessage(MessageBase message) {
+    if (message is! Message) return false;
     return message.flags.any((flag) {
       switch (flag) {
         case MessageFlag.mentioned:
@@ -346,7 +350,8 @@ class StarredMessagesNarrow extends Narrow {
   ApiNarrow apiEncode() => [ApiNarrowIs(IsOperand.starred)];
 
   @override
-  bool containsMessage(Message message) {
+  bool containsMessage(MessageBase message) {
+    if (message is! Message) return false;
     return message.flags.contains(MessageFlag.starred);
   }
 

test/model/narrow_test.dart

@@ -7,6 +7,32 @@ import 'package:zulip/model/narrow.dart';
 import '../example_data.dart' as eg;
 import 'narrow_checks.dart';
 
+/// A [MessageBase] subclass for testing.
+// TODO(#1441): switch to outbox-messages instead
+sealed class _TestMessage<T extends Conversation> extends MessageBase<T> {
+  @override
+  final int? id = null;
+
+  _TestMessage() : super(senderId: eg.selfUser.userId, timestamp: 123456789);
+}
+
+class _TestStreamMessage extends _TestMessage<StreamConversation> {
+  @override
+  final StreamConversation conversation;
+
+  _TestStreamMessage({required ZulipStream stream, required String topic})
+    : conversation = StreamConversation(
+        stream.streamId, TopicName(topic), displayRecipient: null);
+}
+
+class _TestDmMessage extends _TestMessage<DmConversation> {
+  @override
+  final DmConversation conversation;
+
+  _TestDmMessage({required List<int> allRecipientIds})
+    : conversation = DmConversation(allRecipientIds: allRecipientIds);
+}
+
 void main() {
   group('SendableNarrow', () {
     test('ofMessage: stream message', () {
@@ -33,6 +59,13 @@ void main() {
         eg.streamMessage(stream: otherStream, topic: 'topic'))).isFalse();
       check(narrow.containsMessage(
         eg.streamMessage(stream: stream,      topic: 'topic'))).isTrue();
+
+      check(narrow.containsMessage(
+        _TestDmMessage(allRecipientIds: [1]))).isFalse();
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: otherStream, topic: 'topic'))).isFalse();
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: stream,      topic: 'topic'))).isTrue();
     });
   });
 
@@ -56,6 +89,15 @@ void main() {
         eg.streamMessage(stream: stream,      topic: 'topic2'))).isFalse();
       check(narrow.containsMessage(
         eg.streamMessage(stream: stream,      topic: 'topic'))).isTrue();
+
+      check(narrow.containsMessage(
+        _TestDmMessage(allRecipientIds: [1]))).isFalse();
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: otherStream, topic: 'topic'))).isFalse();
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: stream,      topic: 'topic2'))).isFalse();
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: stream,      topic: 'topic'))).isTrue();
     });
   });
 
@@ -176,6 +218,19 @@ void main() {
       check(narrow123.containsMessage(dm(user2, [user1, user3]))).isTrue();
       check(narrow123.containsMessage(dm(user3, [user1, user2]))).isTrue();
     });
+
+    test('containsMessage with non-Message', () {
+      final narrow = DmNarrow(allRecipientIds: [1, 2], selfUserId: 2);
+
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: eg.stream(), topic: 'topic'))).isFalse();
+      check(narrow.containsMessage(
+        _TestDmMessage(allRecipientIds: [2]))).isFalse();
+      check(narrow.containsMessage(
+        _TestDmMessage(allRecipientIds: [2, 3]))).isFalse();
+      check(narrow.containsMessage(
+        _TestDmMessage(allRecipientIds: [1, 2]))).isTrue();
+    });
   });
 
   group('MentionsNarrow', () {
@@ -188,6 +243,11 @@ void main() {
         eg.streamMessage(flags:[MessageFlag.mentioned]))).isTrue();
       check(narrow.containsMessage(
         eg.streamMessage(flags: [MessageFlag.wildcardMentioned]))).isTrue();
+
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: eg.stream(), topic: 'topic'))).isFalse();
+      check(narrow.containsMessage(
+        _TestDmMessage(allRecipientIds: [eg.selfUser.userId]))).isFalse();
     });
   });
 
@@ -199,6 +259,11 @@ void main() {
         eg.streamMessage(flags: []))).isFalse();
       check(narrow.containsMessage(
         eg.streamMessage(flags:[MessageFlag.starred]))).isTrue();
+
+      check(narrow.containsMessage(
+        _TestStreamMessage(stream: eg.stream(), topic: 'topic'))).isFalse();
+      check(narrow.containsMessage(
+        _TestDmMessage(allRecipientIds: [eg.selfUser.userId]))).isFalse();
     });
   });
 }