From 05fbf0eb5b47d4a839cfb911a59fa1bd7e3883eb Mon Sep 17 00:00:00 2001
From: Toad-Dev <748280+Toad-Dev@users.noreply.github.com>
Date: Mon, 20 Dec 2021 09:07:05 -0800
Subject: [PATCH] Fix NPE when pistons extend (#43).

- MixinLevel was needed in <= 1.16 to make sure pending block entities
had a valid world, but in 1.17 and up all block entities have their
world set immediately (after checking that their blockPos is valid).
- Unfortunately, this bug leaves broken pistons in the world :(
A piston will never seem to extend in the block location where the game
hit the NPE, even if other block entities are put in that position
and replaced with a new piston...
---
 .../fabric/mixin/MixinLevel.java              | 59 -------------------
 src/main/resources/computercraft.mixins.json  |  1 -
 2 files changed, 60 deletions(-)
 delete mode 100644 src/main/java/dan200/computercraft/fabric/mixin/MixinLevel.java

diff --git a/src/main/java/dan200/computercraft/fabric/mixin/MixinLevel.java b/src/main/java/dan200/computercraft/fabric/mixin/MixinLevel.java
deleted file mode 100644
index f9132b54e..000000000
--- a/src/main/java/dan200/computercraft/fabric/mixin/MixinLevel.java
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
- * This file is part of ComputerCraft - http://www.computercraft.info
- * Copyright Daniel Ratcliffe, 2011-2021. Do not distribute without permission.
- * Send enquiries to dratcliffe@gmail.com
- */
-package dan200.computercraft.fabric.mixin;
-
-import dan200.computercraft.shared.common.TileGeneric;
-import net.minecraft.world.level.Level;
-import net.minecraft.world.level.block.entity.BlockEntity;
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Inject;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
-
-import javax.annotation.Nullable;
-import java.util.Collection;
-
-/**
- * Horrible bodge to ensure a {@link BlockEntity}'s world is always present when setting a TE during another TE's tick.
- *
- * Forge does this, this is just a bodge to get Fabric in line with that behaviour.
- */
-@Mixin( Level.class )
-public class MixinLevel
-{
-    @Shadow
-    protected boolean tickingBlockEntities;
-
-    @Inject( method = "setBlockEntity", at = @At( "HEAD" ) )
-    public void setBlockEntity( @Nullable BlockEntity entity, CallbackInfo info )
-    {
-        if( entity != null && !entity.isRemoved() && entity.getLevel().isInWorldBounds( entity.getBlockPos() ) && tickingBlockEntities )
-        {
-            setWorld( entity, this );
-        }
-    }
-
-    private static void setWorld( BlockEntity entity, Object world )
-    {
-        if( entity.getLevel() != world && entity instanceof TileGeneric )
-        {
-            entity.setLevel( (Level) world ); //TODO why?
-        }
-    }
-
-    //    @Inject( method = "addBlockEntities", at = @At( "HEAD" ) )
-    public void addBlockEntities( Collection<BlockEntity> entities, CallbackInfo info )
-    {
-        if( tickingBlockEntities )
-        {
-            for( BlockEntity entity : entities )
-            {
-                setWorld( entity, this );
-            }
-        }
-    }
-}
diff --git a/src/main/resources/computercraft.mixins.json b/src/main/resources/computercraft.mixins.json
index 8acb52d3e..9d0594a1f 100644
--- a/src/main/resources/computercraft.mixins.json
+++ b/src/main/resources/computercraft.mixins.json
@@ -8,7 +8,6 @@
 
         "MixinBlock",
         "MixinEntity",
-        "MixinLevel",
         "MixinMatrix4f",
         "MixinServerLevel",
         "MixinServerPlayerGameMode"