Apply same fix to SF's mixin.
@@ -131,7 +131,7 @@ public EnumActionResult processRightClickBlock(EntityPlayer player, World worldI
if (!ItemStack.areItemStacksEqual(oldStack, this.player.getHeldItem(hand))) {
SpongeCommonEventFactory.playerInteractItemChanged = true;
}
- SpongeCommonEventFactory.lastInteractItemOnBlockCancelled = !event.getUseItemResult().asBoolean();
+ SpongeCommonEventFactory.lastInteractItemOnBlockCancelled = event.getUseItemResult() == Tristate.UNDEFINED ? false : !event.getUseItemResult().asBoolean();
TileEntity tileEntity = worldIn.getTileEntity(pos);
if (event.isCancelled()) {
