Migrated llc Lists to be nullable instead of being an empty array

packages/stream_chat/lib/src/client/channel.dart

@@ -1259,7 +1259,9 @@ class Channel {
     if (preferOffline && cid != null) {
       final updatedState = await _client.chatPersistenceClient
           ?.getChannelStateByCid(cid!, messagePagination: messagesPagination);
-      if (updatedState != null && updatedState.messages.isNotEmpty) {
+      if (updatedState != null &&
+          updatedState.messages != null &&
+          updatedState.messages!.isNotEmpty) {
         if (this.state == null) {
           _initState(updatedState);
         } else {
@@ -1570,7 +1572,7 @@ class ChannelClientState {
 
   void _checkExpiredAttachmentMessages(ChannelState channelState) async {
     final expiredAttachmentMessagesId = channelState.messages
-        .where((m) =>
+        ?.where((m) =>
             !_updatedMessagesIds.contains(m.id) &&
             m.attachments.isNotEmpty &&
             m.attachments.any((e) {
@@ -1597,7 +1599,8 @@ class ChannelClientState {
         .map((e) => e.id)
         .toList();
 
-    if (expiredAttachmentMessagesId.isNotEmpty) {
+    if (expiredAttachmentMessagesId != null &&
+        expiredAttachmentMessagesId.isNotEmpty) {
       await _channel._initializedCompleter.future;
       _updatedMessagesIds.addAll(expiredAttachmentMessagesId);
       _channel.getMessagesById(expiredAttachmentMessagesId);
@@ -1607,9 +1610,10 @@ class ChannelClientState {
   void _listenMemberAdded() {
     _subscriptions.add(_channel.on(EventType.memberAdded).listen((Event e) {
       final member = e.member;
+      final existingMembers = channelState.members ?? [];
       updateChannelState(channelState.copyWith(
         members: [
-          ...channelState.members,
+          ...existingMembers,
           member!,
         ],
       ));
@@ -1619,11 +1623,13 @@ class ChannelClientState {
   void _listenMemberRemoved() {
     _subscriptions.add(_channel.on(EventType.memberRemoved).listen((Event e) {
       final user = e.user;
+      final existingMembers = channelState.members ?? [];
+      final existingRead = channelState.read ?? [];
       updateChannelState(channelState.copyWith(
-        members: channelState.members
+        members: existingMembers
             .where((m) => m.userId != user!.id)
             .toList(growable: false),
-        read: channelState.read
+        read: existingRead
             .where((r) => r.user.id != user!.id)
             .toList(growable: false),
       ));
@@ -1793,9 +1799,10 @@ class ChannelClientState {
       updateMessage(message);
 
       if (message.pinned) {
+        final _existingPinnedMessages = _channelState.pinnedMessages ?? [];
         _channelState = _channelState.copyWith(
           pinnedMessages: [
-            ..._channelState.pinnedMessages,
+            ..._existingPinnedMessages,
             message,
           ],
         );
@@ -1931,7 +1938,7 @@ class ChannelClientState {
       )
           .listen(
         (event) {
-          final readList = List<Read>.from(_channelState.read);
+          final readList = List<Read>.from(_channelState.read ?? []);
           final userReadIndex =
               read.indexWhere((r) => r.user.id == event.user!.id);
 
@@ -1952,31 +1959,34 @@ class ChannelClientState {
   }
 
   /// Channel message list.
-  List<Message> get messages => _channelState.messages;
+  List<Message> get messages => _channelState.messages ?? <Message>[];
 
   /// Channel message list as a stream.
   Stream<List<Message>> get messagesStream => channelStateStream
-      .map((cs) => cs.messages)
+      .map((cs) => cs.messages ?? <Message>[])
       .distinct(const ListEquality().equals);
 
   /// Channel pinned message list.
-  List<Message> get pinnedMessages => _channelState.pinnedMessages;
+  List<Message> get pinnedMessages =>
+      _channelState.pinnedMessages ?? <Message>[];
 
   /// Channel pinned message list as a stream.
   Stream<List<Message>> get pinnedMessagesStream => channelStateStream
-      .map((cs) => cs.pinnedMessages)
+      .map((cs) => cs.pinnedMessages ?? <Message>[])
       .distinct(const ListEquality().equals);
 
   /// Get channel last message.
   Message? get lastMessage =>
-      _channelState.messages.isNotEmpty ? _channelState.messages.last : null;
+      _channelState.messages != null && _channelState.messages!.isNotEmpty
+          ? _channelState.messages!.last
+          : null;
 
   /// Get channel last message.
   Stream<Message?> get lastMessageStream =>
       messagesStream.map((event) => event.isNotEmpty ? event.last : null);
 
   /// Channel members list.
-  List<Member> get members => _channelState.members
+  List<Member> get members => (_channelState.members ?? <Member>[])
       .map((e) => e.copyWith(user: _channel.client.state.users[e.user!.id]))
       .toList();
 
@@ -1997,7 +2007,7 @@ class ChannelClientState {
       channelStateStream.map((cs) => cs.watcherCount);
 
   /// Channel watchers list.
-  List<User> get watchers => _channelState.watchers
+  List<User> get watchers => (_channelState.watchers ?? <User>[])
       .map((e) => _channel.client.state.users[e.id] ?? e)
       .toList();
 
@@ -2018,10 +2028,11 @@ class ChannelClientState {
   String? get currentUserRole => currentUserMember?.role;
 
   /// Channel read list.
-  List<Read> get read => _channelState.read;
+  List<Read> get read => _channelState.read ?? <Read>[];
 
   /// Channel read list as a stream.
-  Stream<List<Read>> get readStream => channelStateStream.map((cs) => cs.read);
+  Stream<List<Read>> get readStream =>
+      channelStateStream.map((cs) => cs.read ?? <Read>[]);
 
   bool _isCurrentUserRead(Read read) =>
       read.user.id == _channel._client.state.currentUser!.id;
@@ -2042,7 +2053,7 @@ class ChannelClientState {
 
   /// Setter for unread count.
   set unreadCount(int count) {
-    final reads = [..._channelState.read];
+    final reads = [...read];
     final currentUserReadIndex = reads.indexWhere(_isCurrentUserRead);
 
     if (currentUserReadIndex < 0) return;
@@ -2097,31 +2108,37 @@ class ChannelClientState {
 
   /// Update channelState with updated information.
   void updateChannelState(ChannelState updatedState) {
+    final _existingStateMessages = _channelState.messages ?? [];
+    final _updatedStateMessages = updatedState.messages ?? [];
     final newMessages = <Message>[
-      ...updatedState.messages,
-      ..._channelState.messages
+      ..._updatedStateMessages,
+      ..._existingStateMessages
           .where((m) =>
-              !updatedState.messages.any((newMessage) => newMessage.id == m.id))
+              !_updatedStateMessages.any((newMessage) => newMessage.id == m.id))
           .toList(),
     ]..sort(_sortByCreatedAt);
 
+    final _existingStateWatchers = _channelState.watchers ?? [];
+    final _updatedStateWatchers = updatedState.watchers ?? [];
     final newWatchers = <User>[
-      ...updatedState.watchers,
-      ..._channelState.watchers
+      ..._updatedStateWatchers,
+      ..._existingStateWatchers
           .where((w) =>
-              !updatedState.watchers.any((newWatcher) => newWatcher.id == w.id))
+              !_updatedStateWatchers.any((newWatcher) => newWatcher.id == w.id))
           .toList(),
     ];
 
     final newMembers = <Member>[
-      ...updatedState.members,
+      ...updatedState.members ?? [],
     ];
 
+    final _existingStateRead = _channelState.read ?? [];
+    final _updatedStateRead = updatedState.read ?? [];
     final newReads = <Read>[
-      ...updatedState.read,
-      ..._channelState.read
+      ..._updatedStateRead,
+      ..._existingStateRead
           .where((r) =>
-              !updatedState.read.any((newRead) => newRead.user.id == r.user.id))
+              !_updatedStateRead.any((newRead) => newRead.user.id == r.user.id))
           .toList(),
     ];
 
@@ -2273,9 +2290,9 @@ class ChannelClientState {
     _pinnedMessagesTimer = Timer.periodic(const Duration(seconds: 30), (_) {
       final now = DateTime.now();
       var expiredMessages = channelState.pinnedMessages
-          .where((m) => m.pinExpires?.isBefore(now) == true)
+          ?.where((m) => m.pinExpires?.isBefore(now) == true)
           .toList();
-      if (expiredMessages.isNotEmpty) {
+      if (expiredMessages != null && expiredMessages.isNotEmpty) {
         expiredMessages = expiredMessages
             .map((m) => m.copyWith(
                   pinExpires: null,

packages/stream_chat/lib/src/client/client.dart

@@ -623,7 +623,7 @@ class StreamChatClient {
     final channels = res.channels;
 
     final users = channels
-        .expand((it) => it.members)
+        .expand((it) => it.members ?? <Member>[])
         .map((it) => it.user)
         .toList(growable: false);