From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Thu, 20 May 2021 22:16:37 -0700
Subject: [PATCH] Fix PlayerBucketEmptyEvent result itemstack

Fixes SPIGOT-2560: https://hub.spigotmc.org/jira/projects/SPIGOT/issues/SPIGOT-2560

diff --git a/src/main/java/net/minecraft/world/item/ItemBucket.java b/src/main/java/net/minecraft/world/item/ItemBucket.java
index d126f668828e0788e369294c0b376ef52b344f2c..f97447d77890cd65b5613899c389483bcf82be01 100644
--- a/src/main/java/net/minecraft/world/item/ItemBucket.java
+++ b/src/main/java/net/minecraft/world/item/ItemBucket.java
@@ -118,6 +118,13 @@ public class ItemBucket extends Item {
     }
 
     protected ItemStack a(ItemStack itemstack, EntityHuman entityhuman) {
+        // Paper
+        if (itemLeftInHandAfterPlayerBucketEmptyEvent != null) {
+            ItemStack itemInHand = itemLeftInHandAfterPlayerBucketEmptyEvent;
+            itemLeftInHandAfterPlayerBucketEmptyEvent = null;
+            return itemInHand;
+        }
+        // Paper
         return !entityhuman.abilities.canInstantlyBuild ? new ItemStack(Items.BUCKET) : itemstack;
     }
 
@@ -128,6 +135,7 @@ public class ItemBucket extends Item {
         return a(entityhuman, world, blockposition, movingobjectpositionblock, null, null, null, null);
     }
 
+    private ItemStack itemLeftInHandAfterPlayerBucketEmptyEvent = null; // Paper
     public boolean a(EntityHuman entityhuman, World world, BlockPosition blockposition, @Nullable MovingObjectPositionBlock movingobjectpositionblock, EnumDirection enumdirection, BlockPosition clicked, ItemStack itemstack, EnumHand enumhand) {
         // Paper end
         // CraftBukkit end
@@ -148,6 +156,9 @@ public class ItemBucket extends Item {
                     ((EntityPlayer) entityhuman).getBukkitEntity().updateInventory(); // SPIGOT-4541
                     return false;
                 }
+                // Paper start
+                itemLeftInHandAfterPlayerBucketEmptyEvent = event.getItemStack().equals(CraftItemStack.asNewCraftStack(net.minecraft.world.item.Items.BUCKET)) ? null : CraftItemStack.asNMSCopy(event.getItemStack());
+                // Paper end
             }
             // CraftBukkit end
             if (!flag1) {