MC-136865: Pass original itemstack for enchantment checks on block break

When an itemstack runs out of durability, the amount is reduced to
0 which then marks the item as invalid. This causes the last unit
of durability to not apply enchantments as the enchantment level
check sees the item as a dud.

keep the clone of the item used to a non empty value so it represents
the item used.

Spigot-Server-Patches/0402-MC-136865-Pass-original-itemstack-for-enchantment-ch.patch

@@ -0,0 +1,36 @@
+From 59536510426e4b5b939dcc937a244b20491d48ae Mon Sep 17 00:00:00 2001
+From: MisterVector <whizkid3000@hotmail.com>
+Date: Thu, 1 Nov 2018 14:50:05 -0700
+Subject: [PATCH] MC-136865: Use valid item for enchantment checks on block break
+
+When an itemstack runs out of durability, the amount is reduced to
+0 which then marks the item as invalid. This causes the last unit
+of durability to not apply enchantments as the enchantment level
+check sees the item as a dud.
+
+keep the clone of the item used to a non empty value so it represents
+the item used.
+
+
+diff --git a/src/main/java/net/minecraft/server/PlayerInteractManager.java b/src/main/java/net/minecraft/server/PlayerInteractManager.java
+index 23fc4d8e..dbbd1f33 100644
+--- a/src/main/java/net/minecraft/server/PlayerInteractManager.java
++++ b/src/main/java/net/minecraft/server/PlayerInteractManager.java
+@@ -378,8 +378,13 @@ public class PlayerInteractManager {
+                     itemstack1.a(this.world, iblockdata, blockposition, this.player);
+                     // CraftBukkit start - Check if block should drop items
+                     if (flag && flag1 && event.isDropItems()) {
+-                        ItemStack itemstack2 = itemstack1.isEmpty() ? ItemStack.a : itemstack1.cloneItemStack();
++                        // Paper start - fixes MC-136865
++                        ItemStack itemstack2 = itemstack1.cloneItemStack(true);
+ 
++                        if (itemstack2.isEmpty()) {
++                            itemstack2.add(1);
++                        }
++                        // Paper end
+                         iblockdata.getBlock().a(this.world, this.player, blockposition, iblockdata, tileentity, itemstack2);
+                     }
+                     // CraftBukkit end
+-- 
+2.16.1.windows.4
+