From 3780df5dee4adf98b8ab4468c605979f989d04e7 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 19 Jul 2018 01:23:00 -0400
Subject: [PATCH] Don't process despawn if entity is in a chunk scheduled for
 unload

This won't happen anyways if the user has
"skip ticking for entities in chunks scheduled for unload" turned on,
but if they don't, protect from this instant killing the entity to
keep it vanilla in behavior

a player may teleport away, and trigger instant despawn

diff --git a/src/main/java/net/minecraft/server/EntityInsentient.java b/src/main/java/net/minecraft/server/EntityInsentient.java
index 14d122b22b..7b64ec27c3 100644
--- a/src/main/java/net/minecraft/server/EntityInsentient.java
+++ b/src/main/java/net/minecraft/server/EntityInsentient.java
@@ -617,6 +617,8 @@ public abstract class EntityInsentient extends EntityLiving {
         if (this.persistent) {
             this.ticksFarFromPlayer = 0;
         } else {
+            Chunk currentChunk = getChunkAtLocation(); // Paper
+            if (currentChunk != null && (currentChunk.isUnloading() || currentChunk.scheduledForUnload != null)) return; // Paper
             EntityHuman entityhuman = this.world.findNearbyPlayer(this, -1.0D);
 
             if (entityhuman != null && entityhuman.affectsSpawning) { // Paper - Affects Spawning API
-- 
2.18.0