Hopper below full block pulls items from hopper/chest-minecart on slanted track above and to the side

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I think it's related to MCPE-57637

But I need an approval from someone...

Tal, it's possible. I was also waiting for a helper or mod to give their opinion on that. But the hopper with furnace taking items from outside the furnace's inventory is what has me confused.

So it might be a different problem tho..

Let's wait for a replay from modder or helper.

I don't think this is the same issue as MCPE-57637 because in that report it is a hopper minecart doing the pulling. However, it could be related. Come to think of it, both could be partially due to a problem with the hopper minecart hitbox. Is this still happening in 1.16.0.57 and later?

GoldenHelmet, sorry for the delay, just tested in 1.16.0.60 and it's still doing it. Also tested with chest minecart, and it has an item pulled out like the hopper cart. If the cart is launched slowly it happens every time.

As has been said earlier, this is likely due to the hitbox of the minecart.

Confirmed the unexpected pulling in 1.14.60 with solid blocks above the hopper. As stated in the description, in 1.14.60 it does not occur when blocks with inventory are placed above the hopper. I am not in beta so I cannot test in 1.16 yet, but the video linked in the description shows it clearly enough to confirm. I believe that the 1.14.60 behavior is a bug, and in 1.16 betas it is just worst.

This bug can be reproduced manually by using an unpowered powered rail on the decline, placing the hopper minecart on it, and nudging the hopper minecart until its lower corner is visually halfway down the slanted powered rail. From that point to a couple nudges higher, the hopper below continuously pulls items from the hopper minecart above.

This occurs in every direction, so I would say that the bug is in the hopper/chest-minecart hitbox or the positioning on the inclined rail rather than the hopper block. In that way it is unrelated to the buggy pulling in MCPE-57637.

GoldenHelmet, thanks for confirming. I ran another test to confirm items being pulled by hoppers with inventory above. 1.16.0.60 In the images, a simple water stream pushing items next to the chest causes the items to "enter" the inventory of the hopper below. I say "enter" because the hopper isn't pulling items in one at a time; if you throw a stack into the water stream, as soon as the items get close to the chest the whole stack is instantly put into the hopper's inventory.

@Jonathan Peters hoppers are meant to collect or “suck” free-floating items a stack at a time per MCPE-64628. The reason they get around the chest is that the chest does not have a full collision box. It is smaller than a block so it allows loose items to be within the same block space, where they can be collected by the hopper. However, in 1.14.60 the hopper does not collect items pushed against the side of a chest above it.

Probably the reason blocks with inventory stop collection, and the buggy pulling from hopper/chest minecarts, in 1.14.60 is because hoppers don’t search for items or hopper/chest minecarts if they find an inventory block first. I would guess that the new behavior in recent beta versions is due to the fix for MCPE-54244 in 1.15.0.53.

That's interesting, I never realized that collection was independent of the cool-down time. Good to know. Is this new intended behavior, hoppers pulling from outside of an inventory? As it is, there's no way to "cap" a hopper and prevent free items from going where they're not supposed to.

@Jonathan Peters I do not know if the new behavior of hoppers with inventory blocks above them collecting items or pulling items from hopper/chest minecarts it is intended. My guess would be that it's an unintended consequence of how MCPE-54244 was fixed. It probably should have a separate ticket, since this ticket started off focused on the hopper/chest-minecart-on-a-slanted-track-above issue. The two issues have very different causes. The change to how hoppers handle inventory blocks above is due to a change in the hopper's pulling and collecting functions, while the pulling from diagonally above on a slanted track is due to the position of the hopper/chest-minecart that is being pulled from.

You can verify that the pulling from diagonally above is due to the position of the hopper/chest-minecart like this: break the slanted rail that it sits on and observe that it falls partially inside the block above the hopper. It can be pulled from because it's interaction box (not sure if that's the right name) overlaps the block above the hopper. Like this:

@GoldenHelmet, just letting you know I created a separate ticket here: MCPE-80555 regarding the hopper/container bug

Affects 1.16.20.54 Beta

I have re-thought this report and the companion report on hopper pushing (MCPE-94293) and want to recommend that they be closed Works As Intended or Won't Fix. Both behaviors have always been in the game and both are actually important for advanced storage tech. The only reason they were reported as bugs is because MCPE-80555 / MCPE-109449 caused existing builds to behave differently. Assuming that MCPE-109449 will be fixed, given that MCPE-80555 was fixed 1.16.100, the behavior of hoppers toward hopper/chest-minecarts will once again controllable in traditional ways.

The underlying cause of the issue reported here is that hoppers pull from hopper/chest-minecarts based on the hitbox of the hopper/chest-minecart overlapping the hopper's pulling range. Far from being a problem, this behavior is the basis for builds that overlap hopper/chest-minecarts over 2 or 4 hoppers in order to empty them quickly. If this behavior were removed from the game it would break a lot of advance item transport and storage builds. See the picture below.

Thank you for your report!
However, this issue has been closed as Won't Fix.

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