Fix crashes for extremely long messages with no line breaks (#2163)

changelog.d/2105.bugfix

@@ -0,0 +1 @@
+Fix crashes in room list when the last message for a room was an extremely long one (several thousands of characters) with no line breaks.

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/utils/messagesummary/MessageSummaryFormatterImpl.kt

@@ -42,6 +42,12 @@ import javax.inject.Inject
 class MessageSummaryFormatterImpl @Inject constructor(
     @ApplicationContext private val context: Context,
 ) : MessageSummaryFormatter {
+
+    companion object {
+        // Max characters to display in the summary message. This works around https://github.com/element-hq/element-x-android/issues/2105
+        private const val MAX_SAFE_LENGTH = 500
+    }
+
     override fun format(event: TimelineItem.Event): String {
         return when (event.content) {
             is TimelineItemTextBasedContent -> event.content.plainText
@@ -58,6 +64,6 @@ class MessageSummaryFormatterImpl @Inject constructor(
             is TimelineItemVideoContent -> context.getString(CommonStrings.common_video)
             is TimelineItemFileContent -> context.getString(CommonStrings.common_file)
             is TimelineItemAudioContent -> context.getString(CommonStrings.common_audio)
-        }
+        }.take(MAX_SAFE_LENGTH)
     }
 }

libraries/eventformatter/impl/src/main/kotlin/io/element/android/libraries/eventformatter/impl/DefaultRoomLastMessageFormatter.kt

@@ -63,47 +63,52 @@ class DefaultRoomLastMessageFormatter @Inject constructor(
     private val stateContentFormatter: StateContentFormatter,
 ) : RoomLastMessageFormatter {
 
+    companion object {
+        // Max characters to display in the last message. This works around https://github.com/element-hq/element-x-android/issues/2105
+        private const val MAX_SAFE_LENGTH = 500
+    }
+
     override fun format(event: EventTimelineItem, isDmRoom: Boolean): CharSequence? {
         val isOutgoing = event.isOwn
         val senderDisplayName = (event.senderProfile as? ProfileTimelineDetails.Ready)?.displayName ?: event.sender.value
         return when (val content = event.content) {
-            is MessageContent -> processMessageContents(content, senderDisplayName, isDmRoom)
-            RedactedContent -> {
-                val message = sp.getString(CommonStrings.common_message_removed)
-                if (!isDmRoom) {
-                    prefix(message, senderDisplayName)
-                } else {
-                    message
+                is MessageContent -> processMessageContents(content, senderDisplayName, isDmRoom)
+                RedactedContent -> {
+                    val message = sp.getString(CommonStrings.common_message_removed)
+                    if (!isDmRoom) {
+                        prefix(message, senderDisplayName)
+                    } else {
+                        message
+                    }
                 }
-            }
-            is StickerContent -> {
-                content.body
-            }
-            is UnableToDecryptContent -> {
-                val message = sp.getString(CommonStrings.common_waiting_for_decryption_key)
-                if (!isDmRoom) {
-                    prefix(message, senderDisplayName)
-                } else {
-                    message
+                is StickerContent -> {
+                    content.body
                 }
-            }
-            is RoomMembershipContent -> {
-                roomMembershipContentFormatter.format(content, senderDisplayName, isOutgoing)
-            }
-            is ProfileChangeContent -> {
-                profileChangeContentFormatter.format(content, senderDisplayName, isOutgoing)
-            }
-            is StateContent -> {
-                stateContentFormatter.format(content, senderDisplayName, isOutgoing, RenderingMode.RoomList)
-            }
-            is PollContent -> {
-                val message = sp.getString(CommonStrings.common_poll_summary, content.question)
-                prefixIfNeeded(message, senderDisplayName, isDmRoom)
-            }
-            is FailedToParseMessageLikeContent, is FailedToParseStateContent, is UnknownContent -> {
-                prefixIfNeeded(sp.getString(CommonStrings.common_unsupported_event), senderDisplayName, isDmRoom)
-            }
-        }
+                is UnableToDecryptContent -> {
+                    val message = sp.getString(CommonStrings.common_waiting_for_decryption_key)
+                    if (!isDmRoom) {
+                        prefix(message, senderDisplayName)
+                    } else {
+                        message
+                    }
+                }
+                is RoomMembershipContent -> {
+                    roomMembershipContentFormatter.format(content, senderDisplayName, isOutgoing)
+                }
+                is ProfileChangeContent -> {
+                    profileChangeContentFormatter.format(content, senderDisplayName, isOutgoing)
+                }
+                is StateContent -> {
+                    stateContentFormatter.format(content, senderDisplayName, isOutgoing, RenderingMode.RoomList)
+                }
+                is PollContent -> {
+                    val message = sp.getString(CommonStrings.common_poll_summary, content.question)
+                    prefixIfNeeded(message, senderDisplayName, isDmRoom)
+                }
+                is FailedToParseMessageLikeContent, is FailedToParseStateContent, is UnknownContent -> {
+                    prefixIfNeeded(sp.getString(CommonStrings.common_unsupported_event), senderDisplayName, isDmRoom)
+                }
+            }?.take(MAX_SAFE_LENGTH)
     }
 
     private fun processMessageContents(messageContent: MessageContent, senderDisplayName: String, isDmRoom: Boolean): CharSequence? {