[ECO-5517] Added comprehensive unit tests for liveobjects Helpers

Author: sacOO7

live-objects/src/main/kotlin/io/ably/lib/objects/Helpers.kt

@@ -138,19 +138,20 @@ internal fun LiveObjectsAdapter.throwIfUnpublishableState(channelName: String) {
 }
 
 // Spec: RTO2
-internal fun LiveObjectsAdapter.throwIfMissingChannelMode(channelName: String, channelMode: ChannelMode) {
-  val channelModes = getChannelModes(channelName)
-  if (channelModes == null || !channelModes.contains(channelMode)) {
-    // Spec: RTO2a2, RTO2b2
-    throw ablyException("\"${channelMode.name}\" channel mode must be set for this operation", ErrorCode.ChannelModeRequired)
+private fun LiveObjectsAdapter.throwIfMissingChannelMode(channelName: String, channelMode: ChannelMode) {
+  getChannelModes(channelName)?.let { modes ->
+    if (modes.contains(channelMode)) return // If channel modes are set, check if the required mode is present
   }
+  // Spec: RTO2a2, RTO2b2
+  throw ablyException("\"${channelMode.name}\" channel mode must be set for this operation", ErrorCode.ChannelModeRequired)
 }
 
-internal fun LiveObjectsAdapter.throwIfInChannelState(channelName: String, channelStates: Array<ChannelState>) {
-  val currentState = getChannel(channelName).state
-  if (currentState == null || channelStates.contains(currentState)) {
-    throw ablyException("Channel is in invalid state: $currentState", ErrorCode.ChannelStateError)
+private fun LiveObjectsAdapter.throwIfInChannelState(channelName: String, channelStates: Array<ChannelState>) {
+  val currentChannelState = getChannel(channelName).state
+  currentChannelState?.let {
+    if (!channelStates.contains(it)) return
   }
+  throw ablyException("Channel is in invalid state: $currentChannelState", ErrorCode.ChannelStateError)
 }
 
 internal fun LiveObjectsAdapter.throwIfEchoMessagesDisabled() {