From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sat, 7 Mar 2020 00:07:51 +0000
Subject: [PATCH] Validate tripwire hook placement before update


diff --git a/src/main/java/net/minecraft/world/level/block/BlockTripwireHook.java b/src/main/java/net/minecraft/world/level/block/BlockTripwireHook.java
index 8b24978cb54f2102d61f27038dedc5e3dc392dbc..5e3cf96b813d2871adf7a7f870af6c6a5dd878c1 100644
--- a/src/main/java/net/minecraft/world/level/block/BlockTripwireHook.java
+++ b/src/main/java/net/minecraft/world/level/block/BlockTripwireHook.java
@@ -170,6 +170,7 @@ public class BlockTripwireHook extends Block {
 
         this.a(world, blockposition, flag4, flag5, flag2, flag3);
         if (!flag) {
+            if (world.getType(blockposition).getBlock() == Blocks.TRIPWIRE_HOOK) // Paper - validate
             world.setTypeAndData(blockposition, (IBlockData) iblockdata3.set(BlockTripwireHook.FACING, enumdirection), 3);
             if (flag1) {
                 this.a(world, blockposition, enumdirection);