Mojira Archive
MC-88097

Snow blocks receive (useless) random updates and can get destroyed when there is a light glitch

The bug

I always was under the impression that snow blocks (other than snow layers) are not intended to melt. However, recently I managed to get some to melt when trying to move a giant flying machine.
I would expect snow blocks to not randomly disappear, but instead snow blocks pop out as items under certain conditions.

How to reproduce

  1. Create a new super flat world and don't move while executing these commands
  2. Make sure you are on render distance 16
  3. /gamemode spectator
  4. /tp ~1024 ~ ~
  5. /fill ~ ~-1 ~ ~3 ~-1 ~15 minecraft:glowstone
  6. /fill ~ ~ ~ ~ ~ ~15 minecraft:piston[facing=east]
  7. /fill ~1 ~ ~ ~1 ~ ~15 minecraft:snow_block
  8. /tp ~-256 ~ ~
  9. /fill ~255 ~ ~ ~255 ~ ~15 minecraft:redstone_block
  10. /tp ~256 ~ ~
  11. /gamemode creative
  12. You may move now and see snow blocks disappear. (/gamerule randomTickSpeed 100, to speed it up)

Video demonstrating the issue: https://youtu.be/ZkI3uU7hoBA?t=1m38s

What's going on?

So apparently snow blocks have the same part of code to them that makes snow layers melt. It never comes to play though because it checks for the light level inside the block (which is always 0, unless you cause a light glitch).
It is likely that at some point snow blocks where actually intended to melt but didn't due to the light level.
But please don't make them melt now. I'm someone (and not the only one) who builds a lot with snow. So all the old builds would melt if snow would ever melt.
So my request is to remove this part of code and take snow blocks of the list of tickable blocks (as that currently doesn't do anything anyway).