Only remove blocks when golem is successfully spawned. Fixes BUKKIT-1094

src/main/java/net/minecraft/server/BlockPumpkin.java

@@ -1,6 +1,7 @@
 package net.minecraft.server;
 
 // CraftBukkit start
+import org.bukkit.craftbukkit.util.BlockStateListPopulator;
 import org.bukkit.event.block.BlockRedstoneEvent;
 import org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason;
 // CraftBukkit end
@@ -41,16 +42,20 @@ public class BlockPumpkin extends BlockDirectional {
         if (world.suppressPhysics) return; // CraftBukkit
         if (world.getTypeId(i, j - 1, k) == Block.SNOW_BLOCK.id && world.getTypeId(i, j - 2, k) == Block.SNOW_BLOCK.id) {
             if (!world.isStatic && world.getServer().getServer().spawnAnimals) { // CraftBukkit - make snowmen obey spawning rules
-                world.setRawTypeId(i, j, k, 0);
-                world.setRawTypeId(i, j - 1, k, 0);
-                world.setRawTypeId(i, j - 2, k, 0);
+                // CraftBukkit start - Use BlockStateListPopulator
+                BlockStateListPopulator blockList = new BlockStateListPopulator(world.getWorld());
+
+                blockList.setTypeId(i, j, k, 0);
+                blockList.setTypeId(i, j - 1, k, 0);
+                blockList.setTypeId(i, j - 2, k, 0);
+
                 EntitySnowman entitysnowman = new EntitySnowman(world);
 
                 entitysnowman.setPositionRotation((double) i + 0.5D, (double) j - 1.95D, (double) k + 0.5D, 0.0F, 0.0F);
-                world.addEntity(entitysnowman, SpawnReason.BUILD_SNOWMAN); // CraftBukkit
-                world.update(i, j, k, 0);
-                world.update(i, j - 1, k, 0);
-                world.update(i, j - 2, k, 0);
+                if (world.addEntity(entitysnowman, SpawnReason.BUILD_SNOWMAN)) {
+                    blockList.updateList();
+                }
+                // CraftBukkit end
             }
 
             for (int l = 0; l < 120; ++l) {
@@ -61,37 +66,32 @@ public class BlockPumpkin extends BlockDirectional {
             boolean flag1 = world.getTypeId(i, j - 1, k - 1) == Block.IRON_BLOCK.id && world.getTypeId(i, j - 1, k + 1) == Block.IRON_BLOCK.id;
 
             if (flag || flag1) {
-                world.setRawTypeId(i, j, k, 0);
-                world.setRawTypeId(i, j - 1, k, 0);
-                world.setRawTypeId(i, j - 2, k, 0);
+                // CraftBukkit start - Use BlockStateListPopulator
+                BlockStateListPopulator blockList = new BlockStateListPopulator(world.getWorld());
+
+                blockList.setTypeId(i, j, k, 0);
+                blockList.setTypeId(i, j - 1, k, 0);
+                blockList.setTypeId(i, j - 2, k, 0);
                 if (flag) {
-                    world.setRawTypeId(i - 1, j - 1, k, 0);
-                    world.setRawTypeId(i + 1, j - 1, k, 0);
+                    blockList.setTypeId(i - 1, j - 1, k, 0);
+                    blockList.setTypeId(i + 1, j - 1, k, 0);
                 } else {
-                    world.setRawTypeId(i, j - 1, k - 1, 0);
-                    world.setRawTypeId(i, j - 1, k + 1, 0);
+                    blockList.setTypeId(i, j - 1, k - 1, 0);
+                    blockList.setTypeId(i, j - 1, k + 1, 0);
                 }
 
                 EntityIronGolem entityirongolem = new EntityIronGolem(world);
 
                 entityirongolem.b(true);
                 entityirongolem.setPositionRotation((double) i + 0.5D, (double) j - 1.95D, (double) k + 0.5D, 0.0F, 0.0F);
-                world.addEntity(entityirongolem, SpawnReason.BUILD_IRONGOLEM);
-
+                if (world.addEntity(entityirongolem, SpawnReason.BUILD_IRONGOLEM)) {
                     for (int i1 = 0; i1 < 120; ++i1) {
                         world.a("snowballpoof", (double) i + world.random.nextDouble(), (double) (j - 2) + world.random.nextDouble() * 3.9D, (double) k + world.random.nextDouble(), 0.0D, 0.0D, 0.0D);
                     }
 
-                world.update(i, j, k, 0);
-                world.update(i, j - 1, k, 0);
-                world.update(i, j - 2, k, 0);
-                if (flag) {
-                    world.update(i - 1, j - 1, k, 0);
-                    world.update(i + 1, j - 1, k, 0);
-                } else {
-                    world.update(i, j - 1, k - 1, 0);
-                    world.update(i, j - 1, k + 1, 0);
+                    blockList.updateList();
                 }
+                // CraftBukkit end
             }
         }
     }

src/main/java/org/bukkit/craftbukkit/util/BlockStateListPopulator.java

@@ -1,5 +1,6 @@
 package org.bukkit.craftbukkit.util;
 
+import java.util.ArrayList;
 import java.util.List;
 import org.bukkit.World;
 import org.bukkit.block.BlockState;
@@ -8,6 +9,10 @@ public class BlockStateListPopulator {
     private final World world;
     private final List<BlockState> list;
 
+    public BlockStateListPopulator(World world) {
+        this(world, new ArrayList<BlockState>());
+    }
+
     public BlockStateListPopulator(World world, List<BlockState> list) {
         this.world = world;
         this.list = list;
@@ -19,6 +24,12 @@ public class BlockStateListPopulator {
         list.add(state);
     }
 
+    public void updateList() {
+        for (BlockState state : list) {
+            state.update(true);
+        }
+    }
+
     public List<BlockState> getList() {
         return list;
     }