Hoppers unable to push into hopper minecarts in full block

[sethwheway]

What behaviour is expected:

Hoppers should be able to push items into hopper minecarts as long as they are in range (the vanilla behavior)

What behaviour is observed:

Hopper minecarts are unable to push items into hopper minecarts when the hopper minecart is in a full block (but can for air/transparent blocks)

Steps/models to reproduce:

If the pink concrete is replaced with a transparent block or removed, the hopper is able to push items

Plugin list:

Happens without plugins

Paper version:

This server is running Paper version git-Paper-457 (MC: 1.16.5) (Implementing API version 1.16.5-R0.1-SNAPSHOT)
(Latest)

Anything else:

I am unsure whether this is intentional or just an implementation detail of all the patches to hoppers and minecarts. Anyhow, it is non-vanilla behavior and I see no reason for it to be kept

[sethwheway]

May be related to #4633

[Thibaut040]

I have the same issue. (Using: Paper version git-Paper-584 (MC: 1.16.5) (Implementing API version 1.16.5-R0.1-SNAPSHOT))

[Machine-Maker]

I cannot replicate this on paper 1.18.1. I created the setup displayed, and a hopper from all sides could push into the hopper minecart inside the pink concrete powder block. If there are updated reproduction steps, this can be reopened.

[sethwheway]

I'm able to recreate this fine on a new 1.18.1 paper instance I just spun up. I'm not sure why you'd unable to replicate it.
https://user-images.githubusercontent.com/14334544/149523505-5525c924-0d66-4685-a291-de55e342cbb9.mp4
Let me know if there's anything I can do to help.

[Machine-Maker]

Yeah, you’re right. I must’ve gotten turned around when I compared vanilla to paper server behavior and thought I had just tested on paper, when it was my vanilla testing server. Thanks for catching it.

[Machine-Maker]

So the fix for this right how, is to set hopper.ignore-occluding-blocks in paper.yml to false. I am, however, of the opinion that this should be the default setting to preserve behavior so I think this issue can stay open until that question is resolved.

[sethwheway]

Thank you for the calrification. I see now there is an option to enable this behaviour in 3a43821.
I agree that it should probably be set true by default for parity with vanilla behaviour. Would you like me to update the title of this issue?

[Machine-Maker]

Yeah, edit the original post to reflect that you think the default value should be changed.