From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Byteflux <byte@byteflux.net>
Date: Tue, 1 Mar 2016 15:08:03 -0600
Subject: [PATCH] Remove invalid mob spawner tile entities


diff --git a/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java b/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java
index 485cb87e83dd4b4b052905fb7f5f83d3c26f542f..ee2df7de72c75e4fbf8a681ff254260554969b66 100644
--- a/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java
+++ b/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java
@@ -46,10 +46,12 @@ import net.minecraft.world.level.TickList;
 import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.EntityBlock;
+import net.minecraft.world.level.block.SpawnerBlock;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntityTicker;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.block.entity.TickingBlockEntity;
+import net.minecraft.world.level.block.entity.SpawnerBlockEntity;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.gameevent.EuclideanGameEventDispatcher;
 import net.minecraft.world.level.gameevent.GameEventDispatcher;
@@ -608,6 +610,10 @@ public class LevelChunk implements ChunkAccess {
             }
 
             // CraftBukkit start
+            // Paper start - Remove invalid mob spawner tile entities
+        } else if (blockEntity instanceof SpawnerBlockEntity && !(getBlockState(blockposition).getBlock() instanceof SpawnerBlock)) {
+            this.blockEntities.remove(blockposition);
+            // Paper end
         } else {
             System.out.println("Attempted to place a tile entity (" + blockEntity + ") at " + blockEntity.getBlockPos().getX() + "," + blockEntity.getBlockPos().getY() + "," + blockEntity.getBlockPos().getZ()
                 + " (" + this.getBlockState(blockposition) + ") where there was no entity tile!");