Typing users did not update reliably in the message list because view model did not propagate channel changes to the view (#591)

Author: laevandus

CHANGELOG.md

@@ -5,6 +5,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### 🔄 Changed
 
+### 🐞 Fixed
+- Typing users did not update reliably in the message list [#591](https://github.com/GetStream/stream-chat-swiftui/pull/591)
+
 # [4.62.0](https://github.com/GetStream/stream-chat-swiftui/releases/tag/4.62.0)
 _August 16, 2024_
 

Sources/StreamChatSwiftUI/ChatChannel/ChatChannelViewModel.swift

@@ -120,9 +120,7 @@ open class ChatChannelViewModel: ObservableObject, MessagesDataSource {
         }
     }
 
-    public var channel: ChatChannel? {
-        channelController.channel
-    }
+    @Published public private(set) var channel: ChatChannel?
 
     public var isMessageThread: Bool {
         messageController != nil
@@ -150,6 +148,7 @@ open class ChatChannelViewModel: ObservableObject, MessagesDataSource {
         }
         channelDataSource.delegate = self
         messages = channelDataSource.messages
+        channel = channelController.channel
 
         DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { [weak self] in
             if let scrollToMessage, let parentMessageId = scrollToMessage.parentMessageId, messageController == nil {
@@ -445,6 +444,7 @@ open class ChatChannelViewModel: ObservableObject, MessagesDataSource {
         didUpdateChannel channel: EntityChange<ChatChannel>,
         channelController: ChatChannelController
     ) {
+        self.channel = channel.item
         checkReadIndicators(for: channel)
         checkTypingIndicator()
         checkHeaderType()

StreamChatSwiftUITests/Tests/ChatChannel/ChatChannelViewModel_Tests.swift

@@ -8,7 +8,27 @@ import SwiftUI
 import XCTest
 
 class ChatChannelViewModel_Tests: StreamChatTestCase {
-
+    func test_chatChannelVM_channelIsUpdated() {
+        // Given
+        let cid = ChannelId.unique
+        let initialChannel = ChatChannel.mock(cid: cid)
+        let channelController = makeChannelController()
+        channelController.channel_mock = initialChannel
+        let viewModel = ChatChannelViewModel(channelController: channelController)
+        XCTAssertEqual(initialChannel, viewModel.channel)
+        
+        // When
+        let updatedChannel = ChatChannel.mock(cid: cid)
+        channelController.channel_mock = updatedChannel
+        channelController.delegate?.channelController(
+            channelController,
+            didUpdateChannel: .update(updatedChannel)
+        )
+        
+        // Then
+        XCTAssertEqual(updatedChannel, viewModel.channel)
+    }
+    
     func test_chatChannelVM_messagesLoaded() {
         // Given
         let channelController = makeChannelController()