Compensate for allow-nether/allow-end as false; Fixes BUKKIT-3466

When either of those settings are false, the worlds are not loaded and
therefore will not be targeted for portal exits.  Existing worlds are
iterated directly to avoid defaulting to the first world if a direct
dimension match is not found.

Plugins must also specify exit from custom Bukkit worlds to comply with
original commit: https://github.com/Bukkit/CraftBukkit/commit/2dc2af0

This commit introduces a constant to clarify the dependency on the
CraftBukkit implementation of custom worlds having a dimension offset.

1 files changed, 12 insertions, 2 deletions

diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
index e1d611ed..dffa97fb 100644
--- a/src/main/java/net/minecraft/server/Entity.java
+++ b/src/main/java/net/minecraft/server/Entity.java
@@ -1750,10 +1750,20 @@ public abstract class Entity {
             MinecraftServer minecraftserver = MinecraftServer.getServer();
             // CraftBukkit start - move logic into new function "teleportToLocation"
             // int j = this.dimension;
+            WorldServer exitWorld = null;
+            if (this.dimension < CraftWorld.CUSTOM_DIMENSION_OFFSET) { // plugins must specify exit from custom Bukkit worlds
+                // only target existing worlds (compensate for allow-nether/allow-end as false)
+                for (WorldServer world : minecraftserver.worlds) {
+                    if (world.dimension == i) {
+                        exitWorld = world;
+                    }
+                }
+            }
+
             Location enter = this.getBukkitEntity().getLocation();
-            Location exit = minecraftserver.getPlayerList().calculateTarget(enter, minecraftserver.getWorldServer(i));
+            Location exit = exitWorld != null ? minecraftserver.getPlayerList().calculateTarget(enter, minecraftserver.getWorldServer(i)) : null;
 
-            TravelAgent agent = (TravelAgent) ((CraftWorld) exit.getWorld()).getHandle().s();
+            TravelAgent agent = exit != null ? (TravelAgent) ((CraftWorld) exit.getWorld()).getHandle().s() : null;
             EntityPortalEvent event = new EntityPortalEvent(this.getBukkitEntity(), enter, exit, agent);
             event.getEntity().getServer().getPluginManager().callEvent(event);
             if (event.isCancelled() || event.getTo() == null || !this.isAlive()) {