From d8e05c16c8a0b7598fa490f39ecdc89828fb33a2 Mon Sep 17 00:00:00 2001
From: Geeves <22774890+Geevies@users.noreply.github.com>
Date: Tue, 12 Aug 2025 18:30:44 +0200
Subject: [PATCH] Portal Fix (#21158)

* Fixes telescience portals not working correctly, causing an infinite
loop.
---
 code/datums/helper_datums/teleport.dm | 11 +++++++++++
 html/changelogs/geeves-portal_fix.yml |  6 ++++++
 2 files changed, 17 insertions(+)
 create mode 100644 html/changelogs/geeves-portal_fix.yml

diff --git a/code/datums/helper_datums/teleport.dm b/code/datums/helper_datums/teleport.dm
index ef87073e8f2..4e25a93d9d2 100644
--- a/code/datums/helper_datums/teleport.dm
+++ b/code/datums/helper_datums/teleport.dm
@@ -146,6 +146,14 @@
 
 	playSpecials(curturf,effectin,soundin)
 
+	// we don't want a teleportation loop, if we teleport to a destination that already has a portal
+	// disable it for just a moment until we get there
+	var/has_active_destination_portal = FALSE
+	var/obj/effect/portal/destination_portal = locate() in destturf
+	if(destination_portal?.does_teleport)
+		has_active_destination_portal = TRUE
+		destination_portal.does_teleport = FALSE
+
 	var/obj/structure/bed/stool/chair/C = null
 	if(isliving(teleatom))
 		var/mob/living/L = teleatom
@@ -270,6 +278,9 @@
 
 	destarea.Entered(teleatom)
 
+	if(has_active_destination_portal)
+		destination_portal.does_teleport = TRUE
+
 	return TRUE
 
 /datum/teleport/proc/teleport()
diff --git a/html/changelogs/geeves-portal_fix.yml b/html/changelogs/geeves-portal_fix.yml
new file mode 100644
index 00000000000..db7d3670028
--- /dev/null
+++ b/html/changelogs/geeves-portal_fix.yml
@@ -0,0 +1,6 @@
+author: Geeves
+
+delete-after: True
+
+changes:
+  - bugfix: "Fixes telescience portals not working correctly, causing an infinite loop."