Minecraft 1.9, Minecraft 1.9.1 Pre-Release 3, Minecraft 1.9.1, Minecraft 1.9.2, Minecraft 16w20a, Minecraft 16w21b, Minecraft 16w38a, Minecraft 1.11 Pre-Release 1, Minecraft 1.11, 20w07a
A command block (impulse, unconditional, redstone required) which clones (move) itself, an attached powered block (or redstone wire) and a repeater powering the block (or wire) retriggers immediately after cloning, disappearing into the far distance rapidly.
Place on top of solid blocks (east to west) a command block, any solid block or redstone wire, and a repeater facing east.
Enter the following command into the block:
clone ~-2 ~ ~ ~ ~ ~ ~-1 ~ ~ replace move
Set the command block to impluse, unconditional, redstone required.
Place a redstone torch or other power source in the block immediately west of the repeater.
Expected: The command block, solid block (or wire) and repeater move one block east and stop, being no longer powered.
Observed: the three blocks move rapidly into the distance as the command block is retriggered after each move.
If the assembly is not on a flat plane it will stop when the repeater no longer has a block beneath it.
This implies that it is the state of the cloned repeater that causes the problem.
Replacing the repeater with a button results in a cloned button which is locked in the powered state. In this button-powered setup change the command to
clone ~-2 ~ ~ ~-1 ~ ~ ~-2 ~1 ~ replace
In this case pressing the button results in the button and the block to which it is attached being cloned one place upwards, but the cloned button is locked in the powered state and cannot be pressed.
Further testing shows that cloned pressure plates also remain powered indefinitely.