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  1. Minecraft: Java Edition
  2. MC-87798

Command blocks running before a joining player is fully loaded



    • Bug
    • Resolution: Won't Fix
    • None
    • Minecraft 15w35e, Minecraft 15w36d, Minecraft 15w38b, Minecraft 15w50a, Minecraft 1.9 Pre-Release 3, Minecraft 16w35a, 1.15.2, 20w07a, 1.16 Release Candidate 1, 1.16, 1.16.2
    • Confirmed
    • Creative
    • (Unassigned)


      The bug

      When a player joins a world or server, repeating command blocks begin to run before they are fully loaded into the game.

      What I expected to happen was...

      I expected for the repeating commands blocks to only execute when a player is fully loaded, so that they doesn't falsely execute a successful testfor command.

      What actually happened was...

      A repeating command block checking for a player will fail momentarily, even though the player has joined.

      How to reproduce

      1. On singleplayer, enter the following command in a repeating command block:
        execute unless entity @a run setblock ~ ~1 ~ stone
      2. Exit and rejoin the world
        →  A block of stone has been placed above the command block

      Original steps to Reproduce

      1. Create a new world of any type in creative mode.
      2. Place a repeating, no-redstone, non-conditional command block with the command testfor @a.
      3. In front of that, place a redstone comparator, a solid block, and a redstone torch (on the block).
      4. Adjacent to the redstone torch, place a repeating, redstone-reliant, non-conditional command block with a say command (e.g. say eggplant).
      5. Nothing should happen; this means that the first command block's testfor @a command is successful, preventing the second command block's command from executing.
      6. Exit and rejoin the world. [@] eggplant will be in chat twice, meaning that the command blocks executed for about two ticks before realizing the player existed.

      This is a problem if you have a message that shows up when nobody is on a certain team, or if you want something to run when there are no players online (in a server).


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        Issue Links



              Unassigned Unassigned
              Poyo Poyo Gainz
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