From b07b1a5c853668c5eb7e2510f002fdc62663d64f Mon Sep 17 00:00:00 2001
From: "sentry[bot]" <39604003+sentry[bot]@users.noreply.github.com>
Date: Mon, 1 Jun 2026 12:32:49 +0200
Subject: [PATCH] Fix: Prevent addtimer with qdeleted object in MouseEntered
 (#22557)

* Please describe the intent of your changes in a clear fashion.
This PR addresses an error where `addtimer` was called with a callback
assigned to a `qdeleted` object, specifically observed when
`MouseEntered` was triggered on items that self-delete, such as the
robotic combitool when dropped.

The root cause was that the `QDELETED(src)` check in
`/obj/item/MouseEntered` was performed *after* the `addtimer` call. This
allowed a timer to be registered for an object that was already marked
for deletion.

The fix involves moving the `if(QDELETED(src)) return` statement to
occur *before* any `addtimer` calls within the `MouseEntered` proc. This
ensures that if an item is already deleted, the function returns
immediately, preventing the creation of timers bound to invalid objects.
* Please make sure that, in the case of mapping changes, you include
images of these changes in the PR's description.
* Please make sure to mark your PR as wip or review required by making a
comment with !wip or !review required
* If you include sprites/sounds/... (assets) that you have not created
yourself specify the license and original author below.
* Ensure that you also credit them in the appropriate location /
changelog as specified in the contributor guidelines

### Asset Licenses
The following assets that **have not** been created by myself are
included in this PR:

| Path | Original Author | License |
| --- | --- | --- |
| icons/example.dmi | ExamplePerson (Example Station) | CC0 |


Fixes SERVER-PROD-4F

---------

Co-authored-by: sentry[bot] <39604003+sentry[bot]@users.noreply.github.com>
Co-authored-by: VMSolidus <evilexecutive@gmail.com>
---
 code/game/objects/items.dm                              | 4 ++--
 html/changelogs/hellfirejag-combitool-timer-runtime.yml | 4 ++++
 2 files changed, 6 insertions(+), 2 deletions(-)
 create mode 100644 html/changelogs/hellfirejag-combitool-timer-runtime.yml

diff --git a/code/game/objects/items.dm b/code/game/objects/items.dm
index 361339ec34b..a98d7e1950c 100644
--- a/code/game/objects/items.dm
+++ b/code/game/objects/items.dm
@@ -1328,10 +1328,10 @@ modules/mob/living/carbon/human/life.dm if you die, you will be zoomed out.
 	. = ..()
 	if(in_inventory || in_storage)
 		var/mob/user = usr
-		if(!(user.client.prefs.toggles_secondary & HIDE_ITEM_TOOLTIPS))
-			tip_timer = addtimer(CALLBACK(src, PROC_REF(openTip), location, control, params, user), 8, TIMER_STOPPABLE)
 		if(QDELETED(src))
 			return
+		if(!(user.client.prefs.toggles_secondary & HIDE_ITEM_TOOLTIPS))
+			tip_timer = addtimer(CALLBACK(src, PROC_REF(openTip), location, control, params, user), 8, TIMER_STOPPABLE)
 		if(!(user.client.prefs.toggles_secondary & SEE_ITEM_OUTLINES))
 			return
 		var/mob/living/L = user
diff --git a/html/changelogs/hellfirejag-combitool-timer-runtime.yml b/html/changelogs/hellfirejag-combitool-timer-runtime.yml
new file mode 100644
index 00000000000..8fbb59129e9
--- /dev/null
+++ b/html/changelogs/hellfirejag-combitool-timer-runtime.yml
@@ -0,0 +1,4 @@
+author: Hellfirejag
+delete-after: True
+changes:
+  - bugfix: "Fixed a runtime error on objects caused by timers being created on objects that are already being qdel'ed."