From 9447030cd4d3c0ac72da1279ef4a9e35e9efb594 Mon Sep 17 00:00:00 2001
From: Florian Schmaus <flo@geekplace.eu>
Date: Mon, 20 May 2024 21:45:47 +0200
Subject: [PATCH] [muc] Do not invoke userHasLeft() on nickname change

When the incoming unavailable presence is signalling a nickname
change (303), then do not invoke userHasLeft(), because the user
actually does not leave but instead just changes its nickname.

Note that this would also have had fixed SMACK-942, as it would
resolve the deadlock. However, using a dedicated lock for
changeNickname() still seems sensible, and if its just to avoid a bit
of lock contention.

What this also fixes is that a MultiUserChat does no longer invoke its
listener-based callbacks after a nickname change, as previously, after
a nickname change, the userHasLeft() would have been invoked, which
tears down the listeners. This issue was found with
MultiUserChatOccupantIntegrationTest.mucChangeNicknameInformationTest().
---
 .../java/org/jivesoftware/smackx/muc/MultiUserChat.java    | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/smack-extensions/src/main/java/org/jivesoftware/smackx/muc/MultiUserChat.java b/smack-extensions/src/main/java/org/jivesoftware/smackx/muc/MultiUserChat.java
index 999a7d306..5c3f687c4 100644
--- a/smack-extensions/src/main/java/org/jivesoftware/smackx/muc/MultiUserChat.java
+++ b/smack-extensions/src/main/java/org/jivesoftware/smackx/muc/MultiUserChat.java
@@ -258,13 +258,14 @@ public class MultiUserChat {
                     break;
                 case unavailable:
                     occupantsMap.remove(from);
-                    if (mucUser != null && mucUser.hasStatus()) {
-                        if (isUserStatusModification) {
+                    Set<Status> status = mucUser.getStatus();
+                    if (mucUser != null && !status.isEmpty()) {
+                        if (isUserStatusModification && !status.contains(MUCUser.Status.NEW_NICKNAME_303)) {
                             userHasLeft();
                         }
                         // Fire events according to the received presence code
                         checkPresenceCode(
-                            mucUser.getStatus(),
+                            status,
                             isUserStatusModification,
                             mucUser,
                             from);