Fix panic by using matterclient calls in the right place. Related to cb7278eb (mattermost). Closes #491

bridge/mattermost/mattermost.go

@@ -185,9 +185,6 @@ func (b *Bmattermost) handleMatter() {
 	for message := range messages {
 		message.Avatar = helper.GetAvatar(b.avatarMap, message.UserID, b.General)
 		message.Account = b.Account
-		if nick := b.mc.GetNickName(message.UserID); nick != "" {
-			message.Username = nick
-		}
 		message.Text, ok = b.replaceAction(message.Text)
 		if ok {
 			message.Event = config.EVENT_USER_ACTION
@@ -256,6 +253,11 @@ func (b *Bmattermost) handleMatterClient(messages chan *config.Message) {
 				}
 			}
 		}
+		// Use nickname instead of username if defined
+		if nick := b.mc.GetNickName(rmsg.UserID); nick != "" {
+			rmsg.Username = nick
+		}
+
 		messages <- rmsg
 	}
 }