SPIGOT-6093: Can't change ItemStack in EntityPickupItemEvent

nms-patches/EntityItem.patch

@@ -85,7 +85,7 @@
              this.velocityChanged();
              this.f = (int) ((float) this.f - f);
              if (this.f <= 0) {
-@@ -285,6 +307,40 @@
+@@ -285,6 +307,45 @@
              Item item = itemstack.getItem();
              int i = itemstack.getCount();
  
@@ -113,6 +113,11 @@
 +                    return;
 +                }
 +
++                // Update the ItemStack incase it was changed in the event
++                itemstack = this.getItemStack();
++                canHold = entityhuman.inventory.canHold(itemstack);
++                remaining = itemstack.getCount() - canHold;
++
 +                itemstack.setCount(canHold + remaining); // = i
 +
 +                // Possibly < 0; fix here so we do not have to modify code below
@@ -126,7 +131,7 @@
              if (this.pickupDelay == 0 && (this.owner == null || this.owner.equals(entityhuman.getUniqueID())) && entityhuman.inventory.pickup(itemstack)) {
                  entityhuman.receive(this, i);
                  if (itemstack.isEmpty()) {
-@@ -328,7 +384,9 @@
+@@ -328,7 +389,9 @@
      }
  
      public void setItemStack(ItemStack itemstack) {