From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 19 Dec 2016 23:07:42 -0500
Subject: [PATCH] Prevent Pathfinding out of World Border

This prevents Entities from trying to run outside of the World Border

TODO: This doesn't prevent the pathfinder from using blocks outside the world border as nodes. We can fix this
by adding code to all overrides in:
    NodeEvaluator:
    public abstract BlockPathTypes getBlockPathType(BlockGetter world, int x, int y, int z);

to return BLOCKED if it is outside the world border.

diff --git a/src/main/java/net/minecraft/world/entity/ai/navigation/PathNavigation.java b/src/main/java/net/minecraft/world/entity/ai/navigation/PathNavigation.java
index 4335bd9d6413d56326be573f7c07c8cd0503d352..9fba89aa8b1c257cdc3a63a5bd137320d66a37ec 100644
--- a/src/main/java/net/minecraft/world/entity/ai/navigation/PathNavigation.java
+++ b/src/main/java/net/minecraft/world/entity/ai/navigation/PathNavigation.java
@@ -155,7 +155,7 @@ public abstract class PathNavigation {
             // Paper start - Pathfind event
             boolean copiedSet = false;
             for (BlockPos possibleTarget : positions) {
-                if (!new com.destroystokyo.paper.event.entity.EntityPathfindEvent(this.mob.getBukkitEntity(),
+                if (!this.mob.getCommandSenderWorld().getWorldBorder().isWithinBounds(possibleTarget) || !new com.destroystokyo.paper.event.entity.EntityPathfindEvent(this.mob.getBukkitEntity(), // Paper - don't path out of world border
                     MCUtil.toLocation(this.mob.level, possibleTarget), target == null ? null : target.getBukkitEntity()).callEvent()) {
                     if (!copiedSet) {
                         copiedSet = true;