Fix composer allowing whitespace only messages to be sent

CHANGELOG.md

@@ -11,6 +11,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 ### 🐞 Fixed
 - Fix an issue where member role sent from backend was not recognized by the SDK [#1288](https://github.com/GetStream/stream-chat-swift/pull/1288)
 - Fix crash in `ChannelListUpdater` caused by the lifetime not aligned with `ChatClient` [#1289](https://github.com/GetStream/stream-chat-swift/pull/1289)
+- Fix composer allowing sending whitespace only messages [#1293](https://github.com/GetStream/stream-chat-swift/issues/1293)
 
 ### 🔄 Changed
 

Sources/StreamChatUI/Composer/ComposerVC.swift

@@ -63,7 +63,7 @@ open class _ComposerVC<ExtraData: ExtraDataTypes>: _ViewController,
 
         /// A boolean that checks if the message contains any content.
         public var isEmpty: Bool {
-            text.isEmpty && attachments.isEmpty
+            text.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty && attachments.isEmpty
         }
 
         /// A boolean that checks if the composer is replying in a thread
@@ -386,7 +386,7 @@ open class _ComposerVC<ExtraData: ExtraDataTypes>: _ViewController,
         if let command = content.command {
             text = "/\(command.name) " + content.text
         } else {
-            text = content.text
+            text = content.text.trimmingCharacters(in: .whitespacesAndNewlines)
         }
 
         if let editingMessage = content.editingMessage {