PaperMC/paper-server/nms-patches/net/minecraft/world/level/block/BlockPumpkinCarved.patch

--- a/net/minecraft/world/level/block/BlockPumpkinCarved.java
+++ b/net/minecraft/world/level/block/BlockPumpkinCarved.java
@@ -24,6 +24,10 @@
 import net.minecraft.world.level.block.state.predicate.BlockStatePredicate;
 import net.minecraft.world.level.block.state.properties.BlockStateDirection;
 
+// CraftBukkit start
+import org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason;
+// CraftBukkit end
+
 public class BlockPumpkinCarved extends BlockFacingHorizontal {
 
     public static final MapCodec<BlockPumpkinCarved> CODEC = simpleCodec(BlockPumpkinCarved::new);
@@ -86,9 +90,14 @@
     }
 
     private static void spawnGolemInWorld(World world, ShapeDetector.ShapeDetectorCollection shapedetector_shapedetectorcollection, Entity entity, BlockPosition blockposition) {
-        clearPatternBlocks(world, shapedetector_shapedetectorcollection);
+        // clearPatternBlocks(world, shapedetector_shapedetectorcollection); // CraftBukkit - moved down
         entity.moveTo((double) blockposition.getX() + 0.5D, (double) blockposition.getY() + 0.05D, (double) blockposition.getZ() + 0.5D, 0.0F, 0.0F);
-        world.addFreshEntity(entity);
+        // CraftBukkit start
+        if (!world.addFreshEntity(entity, (entity.getType() == EntityTypes.SNOW_GOLEM) ? SpawnReason.BUILD_SNOWMAN : SpawnReason.BUILD_IRONGOLEM)) {
+            return;
+        }
+        clearPatternBlocks(world, shapedetector_shapedetectorcollection); // CraftBukkit - from above
+        // CraftBukkit end
         Iterator iterator = world.getEntitiesOfClass(EntityPlayer.class, entity.getBoundingBox().inflate(5.0D)).iterator();
 
         while (iterator.hasNext()) {