Many automatic crafter contraptions use comparators to detect sufficient ingredients in the crafter block and send a redstone signal to activate the crafter. A contraption set up like this to craft single-ingredient recipes can break if a player closes and reopens the world while it is receiving items at a pace that is fully reliable otherwise. This applies to the simplest possible autocrafter, which consists of a hopper feeding the crafter block, and a comparator reading the crafter's fill level and powering a line of dust that points back to the crafter. This is what it looks like:
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Steps to reproduce
Load
. This world consists of 8 basic auto-crafters. The crafter blocks have 8 slots locked so that they can craft single-ingredient recipes. They are disabled by power from a lever that passes from crafter to crafter through repeaters.
Drop a stack of bones on top of each hopper.
Flip the lever to enable the autocrafters. The repeaters cause each autocrafter to start one redstone tick after the one before it.
Observe that each autocrafter is crafting bonemeal.
Save and Quit.
Reopen the world.
Expected results
The autocrafters continue crafting.
Observed results
Some of the autocrafters break, accumulating bones in the crafting slot.
Related issues
testing discovered
Attachments
Comments
migrated
migrated
GoldenHelmet
This issue likely has the same cause as MCPE-179412 and some or all of the cases of MCPE-29548. As detailed in the code analysis on MCPE-179412, the sequence of redstone-tick/non-redstone-tick resets when the world is reloaded. This can result in the world running redstone ticks in consecutive game ticks (the final tick before close, and the first tick upon opening). Any events synchronized to the global redstone system before the relog, such as pending ticks and hopper cooldowns, may become desynchronized from the redstone system, causing contraptions to behave in unexpected ways.
Invisible826
Can confirm in latest preview.
JervieA20
Also occurs in Android device
GoldenHelmet
I have determined that this issue is mostly caused by the behavior described in MCPE-180268. The redstone powering the crafters does not update for several ticks during world loading while the hoppers continue operating.
The issue mentioned in the comments on MCPE-179412 (redstone ticks randomly reassign to odd or even game ticks on world load) may still be a factor.
[Mod] OcelotOnesie
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
Please note, that mechanics of the game may change between updates.
Things such as graphics, sounds, world creation, biomes, redstone, villagers, and animals may not work the same in current versions.
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