From 315d287446bc399710370a95b2299b356c527d20 Mon Sep 17 00:00:00 2001
From: fira <loyauflorian@gmail.com>
Date: Thu, 19 Oct 2023 21:40:43 +0200
Subject: [PATCH] Fixes deleted mobs not unbuckling (#4717)

# About the pull request

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This makes mobs unbuckle on deletion.

Why this matters:
 - Leftover references as buckled_mob on the buckled object
- The object cannot be used by someone else, since someone is still
buckled to it
- In most extreme case eg. shuttle chairs, the shuttle will pull the
deleted mob out of nullspace and back to chair when traveling

# Explain why it's good for the game
Less bugs and less confused admins having to re-spawn an entire tank
over it

# Testing Photographs and Procedure
Tested buckling/deleting without errors
---
 code/game/objects/objs.dm | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/code/game/objects/objs.dm b/code/game/objects/objs.dm
index 184fc51bd507..3fa16af05875 100644
--- a/code/game/objects/objs.dm
+++ b/code/game/objects/objs.dm
@@ -226,9 +226,14 @@
 /obj/proc/afterbuckle(mob/M as mob) // Called after somebody buckled / unbuckled
 	handle_rotation()
 	SEND_SIGNAL(src, COSMIG_OBJ_AFTER_BUCKLE, buckled_mob)
+	if(!buckled_mob)
+		UnregisterSignal(M, COMSIG_PARENT_QDELETING)
+	else
+		RegisterSignal(buckled_mob, COMSIG_PARENT_QDELETING, PROC_REF(unbuckle))
 	return buckled_mob
 
 /obj/proc/unbuckle()
+	SIGNAL_HANDLER
 	if(buckled_mob && buckled_mob.buckled == src)
 		buckled_mob.buckled = null
 		buckled_mob.anchored = initial(buckled_mob.anchored)