Paper/patches/server/0281-Dont-block-Player-remove-if-the-handle-is-a-custom-p.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Zach Brown <zach@zachbr.io>
Date: Mon, 4 Feb 2019 23:33:24 -0500
Subject: [PATCH] Dont block Player#remove if the handle is a custom player

Upstream throws UOE if you try to call remove on a Player.
We just add a check to ensure that the CraftPlayer's handle
is a ServerPlayer

diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
index 24b08196d160feaa7b4409151fcd98cece19892e..1c8e4e3c53acc1c3043cb015cbe504f4cfb7a35c 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
@@ -205,8 +205,12 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
 
     @Override
     public void remove() {
+        if (this.getHandle().getClass().equals(ServerPlayer.class)) { // special case for NMS plugins inheriting
         // Will lead to an inconsistent player state if we remove the player as any other entity.
         throw new UnsupportedOperationException(String.format("Cannot remove player %s, use Player#kickPlayer(String) instead.", this.getName()));
+        } else {
+            super.remove();
+        }
     }
 
     @Override