Despite the "left side bias" introduced in this snapshot redstone will randomly ignore it.
Reproduction Steps
Build this setup
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Hold right click to keep pressing the button
Observed results
Right side piston sometimes activates
Expected Results
Only the left side piston would ever activate
Extra info
For some reason the left side bias has a higher chance of failing with a button as the power source. If you replace it with a lever for example and flick it rapidly the right side piston will activate very rarely
Linked issues
is duplicated by 3
Attachments
Comments 8
This happens when you press the button again while the left piston is retracting. In this state the block position in the middle is unoccupied but the left piston cannot extend yet, so the right piston can extend instead. So, no bug here.
edit: Also, it's basically a duplicate of MC-275318, where this was already explained.
This may be true but I'd prefer if mojang looked at this themselves and determine if it's WAI or not once and for all instead of speculating.
[media][media]
this happens due to pressing the button while one of the pistons is on cooldown, this has nothing to do with update order
This behavior occurs without the redstone experiment enabled. As previously mentioned, this may be expected behavior based off of the fact that the pistons can't extend when the other is still in the middle space before retracting:
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The aim is to make all contraptions possible to rotate in all orientations and work the same while avoiding randomness as much as possible.
In the example you provided, the left piston may still be in cooldown / in its retraction phase, causing it to be unable to extend, while the right piston is able to extend. However, there is no actual randomness involved. If you give the same two pulses with the same pulse lengths, the result will be deterministic, no matter the location or orientation. The only gurantee that is being made is a deterministic update order, whether the block is actually able to respond to that update is not.
Thank you for your report!
After consideration, the issue is being closed as Working as Intended.
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Can confirm, although for some reason i can only reproduce this issue by either holding right click, while looking at a button, or "spamming" it.