Moving blocks update order is HashMap based, causing unreliable behavior

This is sad😞

why do you think observers' order is HashMap based?

In fact it isn't. Its order is always reliable.

The order of updates from blocks pulled or pushed by a piston is HashMap based, not the observors.

observer update order is directional, not locational. It goes X -> Z -> Y negative to positive. 

@CHANAK GAUTAM yes. however it is not relevant to  this report

This bug is due to the piston code that read from a hash map when removing leftover blocks after creating moving blocks

I am able to confirm this in 1.17.1

The Bug:

Observers reading blocks getting pulled are locational, meaning the update order from observers is not reliable in specific cases.

Steps to Reproduce:

• Build the setup shown in the image.

• Set the command blocks to /say 1, /say 2, and /say 3.

• Activate the piston and note the order that the numbers are said.

• Test in multiple locations and note the differences.

Observed Behavior:

The order of numbers differs based on location, this is due to the piston code that reads from a hash map when removing leftover blocks after creating moving blocks.

Expected Behavior:

The order would always be the same, thus being predicable and reliable.

can confirm in 1.18.1