[1.8] IInventory#isItemValidForSlot

When exacly is this called?

I've been making code overwiew and noticed this is never called.

Structure:

ExtendedInventory implements IInventory

ExtendedInventoryContainer extends Container

ExtendedInventorySlot extends Slot

IInventory size is 11.

Container has 11 slots (all use ExtendedInventorySlot)

ExtendedInventorySlot has 2 methods:

public boolean isItemValid(ItemStack stack)

public boolean canTakeStack(EntityPlayer player)

Both of these methods work, on server and on client, they check everything nicely.

I can't find ANY situation in which IInventory#isItemValidForSlot is called. Tried to look at callback but that is not helpful.

From what I am looking at:

- I assume that IInventory#isItemValidForSlot should be used if you want to access IInventory slots without container and is not called anywhere directly by vanilla, but left for custom usage (by mod itself) - only Hopper (tileentity) seems to use it.

Is that correct?

EDIT

If anyone's wondering - I am asking because normally when you put a method in an interface (IInventory) it is being used internally (by vanilla), in this case I am confused because it looks like it's not.