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  1. Minecraft: Java Edition
  2. MC-123311

Pistons moving blocks do not properly update surrounding blocks


    • Icon: Bug Bug
    • Resolution: Unresolved
    • None
    • Minecraft 17w50a, Minecraft 18w01a, Minecraft 18w02a, Minecraft 18w07c, Minecraft 1.13-pre2, 1.15.2, 1.16.2, 1.16.4, 20w46a, 20w51a, 21w03a, 1.16.5, 21w05b, 21w07a, 1.17 Pre-release 1, 1.17.1, 1.19.2
    • Confirmed
    • Redstone
    • Normal
    • Platform

      Usually when a powered rail, detector rail or activator rail gets destroyed it sends out block updates to the blocks diagonally below it.

      In 17w50a, when you have a powered/detector/activator rail and you push it away with a piston, then it does not send out block updates diagonally below it.

      This can cause some blocks to get into invalid states.

      In Rail before.png you see a contraption. If you flick the lever, then you get Rail after.png . In this picture the powered rail on the lower block is in an invalid state because it´s on even though it is not powered by anything. That rail should have been updated when the upper powered rail was pushed away, but it wasn´t.

      (Also this is not a duplicate of MC-96224, because the bug I´m describing here was newly introduced in the 1.13 snapshots and didn´t exist before, while MC-96224 is older, and secondly this bug is about block updates missing when a rail starts being pushed, while MC-96224 is about block updates missing when a rail finishes being pushed).

      This affects the following situations:

      • powered rails do not update their powered state
      • stairs do not update the shape
      • fences/walls/glass panes/iron bars do not update connections
      • support requiring blocks do not drop
      • gravity affected blocks do not fall
      • activated detector rails do not unpower redstone dust
      • redstone stays attached to wall

      Also: https://gfycat.com/FirstMeagerGibbon

            Unassigned Unassigned
            Myren Myren Eario
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