[MCPE-16314] Blocks are rarely deleted when pushed by a piston, and pushing something that was pulled.

Edit: Fixed as of 0.15.3 or 0.15.4

on occasion, when a block pushes a different block that is simultaneously pulled by a slime block, the block that pushed will cease to exist. Here is a diagram:
> = piston s = slime
0 = block x = vanishing block

>x0
>0s

Power the pistons simultaneously, and the x block might disappear

This only happens at certain points in the world, and those points change at reload. A simple way to recreate this bug is to make the flying machine shown in the picture, and wait for it to break. The flying machine will bounce back and forth between the two bedrock until one of the observers disappear. If this fails to happen, reload the world, and try again. It shouldn't take too long

This does not duplicate MCPE-14654 as any block can disapear, not just a piston.

This does not duplicate MCPE-15268 as the blocks are permanatly gone, not just temporaraly.

This may duplicate MCPE-14772 but that is marked as a duplicite of MCPE-14522 and I see no relation between this and MCPE-14522

Linked issues

relates to 2

MCPE-14772 Pistons Delete's Blocks Resolved

MCPE-34549 Deleting command blocks with redstone contraption Resolved

Attachments

Minecraft 1_22_2018 6_55_52 PM.mp4

The diagram, and method of powering the blocks at the same time.png

Comments 6

Samuel Finch 2016-07-20T21:48:14Z

Oh, I forgot to add to the pictures that the four outer pistons are not sticky, and the two inner ones are. like this

O = observer S = Slime
P = piston # = sticky piston

OP OPO
SO#SSS
SSS#OS
OPO PO

PHO 2016-07-22T00:07:16Z

Confirmed on 0.15.2 / iOS. An observer indeed vanished after the machine bounced a couple of times.

(BTW your report is excellent! I want to say as a moderator this is the best bug report I've ever seen. And thank you very much for sharing your great design of bidirectional flying machine and the method of activating two pistons at the same time. I'm really impressed.)

Samuel Finch 2016-07-29T15:28:50Z

Issue has been resolved as of 0.15.3 or 0.15.4 (i don't know wich)

husky2490 2018-01-23T01:00:28Z

I think I've encountered this in 1.2.9
Edit: might not be this issue but a related one

[media]

husky2490 2018-01-24T03:42:30Z

Stroke-by-stroke analysis:
Stroke 1 (back stroke): piston moves with the machine.
Stroke 2 (forward stroke): piston moves with the machine.
Stroke 3: piston moves with the machine.
Stroke 3.5: piston extends.
Stroke 4: piston retracts and arm clips into quartz block, unknown behavior upon clipping.
Stroke 5: piston retracts and deletes quartz block

The same machine in a slightly different configuration showing another bug (might be related)

Austin Danwell 2018-05-23T09:15:56Z

Something similar happens to me exepts with no slime blocks. full blocks seem to be destroyed by sticky pistons with when the full blocks have snow layers on top and the sticky pistons are on a fast redstine clock.