Hopper don't transfer if full and wrong destination for TransferInventoryEvent.Pre

[AlexandreArcil]

Versions

SpongeAPI: 10.0.0-SNAPSHOT
Sponge: 1.19.4-10.0.0-SNAPSHOT
SpongeVanilla: 1.19.4-10.0.0-RC0

The bug

A hopper didn't transfer its items if its 5 slots were filled with a full stack of items (example: 64 oak woods per slot).
Furthermore, the event TransferInventoryEvent.Pre had the same source and destination inventory.
This bug was reported by the issue #3883.

Description

Before transferring its items to the container in its direction, it checks that the container is not full. The check method HopperBlockEntity#isFullContainer was redirected to the mixin method HopperBlockEntityMixin_Inventory#impl$throwTransferPreIfNotFull to capture the transfer and create a TransferInventoryEvent.Pre event. The problem was that the check performed by HopperBlockEntityAccessor.invoker$isFullContainer was called with the hopper container and not the 'attached container' (the container in the hopper direction, such as a chest). In addition, the event TransferInventoryEvent.Pre was created with the same source and destination container (the hopper).

The fix

HopperBlockEntityMixin_Inventory#impl$throwTransferPreIfNotFull had two containers as arguments: the attached container and the hopper container. I just replaced the container argument of HopperBlockEntityAccessor.invoker$isFullContainer with the attached container. Its name was var0 but I renamed it to 'attachedContainer' like the method HopperBlockEntity#getAttachedContainer.

For the event, I just replaced the destination container with the attached container.