Fix a whole bunch of bugs

build.gradle

@@ -189,7 +189,7 @@ processResources {
     inputs.property "commithash", hash
 
     from(sourceSets.main.resources.srcDirs) {
-        include 'fabric.mods.json'
+        include 'fabric.mod.json'
         include 'data/computercraft/lua/rom/help/credits.txt'
 
         expand 'version': mod_version,
@@ -198,7 +198,7 @@ processResources {
     }
 
     from(sourceSets.main.resources.srcDirs) {
-        exclude 'fabric.mods.json'
+        exclude 'fabric.mod.json'
         exclude 'data/computercraft/lua/rom/help/credits.txt'
     }
 }
@@ -250,7 +250,7 @@ curseforge {
     project {
         id = '282001'
         addGameVersion '1.14-Snapshot'
-        releaseType = 'alpha'
+        releaseType = 'beta'
         changelog = "Release notes can be found on the GitHub repository (https://github.com/SquidDev-CC/CC-Tweaked/releases/tag/v${mc_version}-${mod_version})."
     }
 }

gradle.properties

@@ -1,5 +1,5 @@
 # Mod properties
-mod_version=1.82.3
+mod_version=1.82.4
 
 # Minecraft properties
 mc_version=1.14

src/main/java/dan200/computercraft/client/ClientRegistry.java

@@ -12,14 +12,19 @@ import dan200.computercraft.shared.media.items.ItemDisk;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
 import dan200.computercraft.shared.util.Colour;
 import net.fabricmc.fabric.api.client.render.ColorProviderRegistry;
+import net.fabricmc.fabric.api.event.client.ClientSpriteRegistryCallback;
 import net.minecraft.client.MinecraftClient;
 import net.minecraft.client.render.model.BakedModel;
 import net.minecraft.client.render.model.ModelLoader;
 import net.minecraft.client.render.model.ModelRotation;
 import net.minecraft.client.render.model.UnbakedModel;
 import net.minecraft.client.texture.SpriteAtlasTexture;
+import net.minecraft.client.util.ModelIdentifier;
+import net.minecraft.resource.ResourceManager;
+import net.minecraft.util.Identifier;
 
 import java.util.HashSet;
+import java.util.function.Consumer;
 
 /**
  * Registers textures and models for items.
@@ -57,56 +62,22 @@ public final class ClientRegistry
 
     private ClientRegistry() {}
 
-    /*
+    public static void onTextureStitchEvent( SpriteAtlasTexture atlasTexture, ClientSpriteRegistryCallback.Registry registry )
-    TODO: @SubscribeEvent
-    public static void registerModels( ModelRegistryEvent event )
     {
-        ModelLoaderRegistry.registerLoader( TurtleModelLoader.INSTANCE );
-    }
-
-    TODO: @SubscribeEvent
-    public static void onTextureStitchEvent( TextureStitchEvent.Pre event )
-    {
-        ResourceManager manager = MinecraftClient.getInstance().getResourceManager();
         for( String extra : EXTRA_TEXTURES )
         {
-            event.getMap().registerSprite( manager, new Identifier( ComputerCraft.MOD_ID, extra ) );
+            registry.register( new Identifier( ComputerCraft.MOD_ID, extra ) );
         }
     }
 
-    TODO: @SubscribeEvent
+    public static void onModelBakeEvent( ResourceManager manager, Consumer<ModelIdentifier> out )
-    public static void onModelBakeEvent( ModelBakeEvent event )
     {
-        // Load all extra models
-        ModelLoader loader = event.getModelLoader();
-        Map<ModelIdentifier, BakedModel> registry = event.getModelRegistry();
-
         for( String model : EXTRA_MODELS )
         {
-            BakedModel bakedModel = bake( loader, loader.getOrLoadModel( new Identifier( ComputerCraft.MOD_ID, "item/" + model ) ) );
+            out.accept( new ModelIdentifier( new Identifier( ComputerCraft.MOD_ID, model ), "inventory" ) );
-
-            if( bakedModel != null )
-            {
-                registry.put(
-                    new ModelIdentifier( new Identifier( ComputerCraft.MOD_ID, model ), "inventory" ),
-                    bakedModel
-                );
         }
     }
 
-        // And load the custom turtle models in too.
-        registry.put(
-            new ModelIdentifier( new Identifier( ComputerCraft.MOD_ID, "turtle_normal" ), "inventory" ),
-            bake( loader, TurtleModelLoader.INSTANCE.loadModel( new Identifier( ComputerCraft.MOD_ID, "item/turtle_normal" ) ) )
-        );
-
-        registry.put(
-            new ModelIdentifier( new Identifier( ComputerCraft.MOD_ID, "turtle_advanced" ), "inventory" ),
-            bake( loader, TurtleModelLoader.INSTANCE.loadModel( new Identifier( ComputerCraft.MOD_ID, "item/turtle_advanced" ) ) )
-        );
-    }
-    */
-
     public static void onItemColours()
     {
         ColorProviderRegistry.ITEM.register(

src/main/java/dan200/computercraft/client/gui/GuiComputer.java

@@ -19,6 +19,7 @@ import net.minecraft.container.Container;
 import net.minecraft.entity.player.PlayerInventory;
 import net.minecraft.text.StringTextComponent;
 import net.minecraft.util.Identifier;
+import org.lwjgl.glfw.GLFW;
 
 public class GuiComputer<T extends Container> extends ContainerScreen<T>
 {
@@ -141,9 +142,18 @@ public class GuiComputer<T extends Container> extends ContainerScreen<T>
         drawMouseoverTooltip( mouseX, mouseY );
     }
 
+    @Override
+    public boolean keyPressed( int key, int scancode, int modifiers )
+    {
+        // When pressing tab, send it to the computer first
+        return (key == GLFW.GLFW_KEY_TAB && getFocused() == terminalWrapper && terminalWrapper.keyPressed( key, scancode, modifiers ))
+            || super.keyPressed( key, scancode, modifiers );
+    }
+
     @Override
     public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
     {
+        // Make sure drag events are propagated to children
         return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
             || super.mouseDragged( x, y, button, deltaX, deltaY );
     }
@@ -151,6 +161,7 @@ public class GuiComputer<T extends Container> extends ContainerScreen<T>
     @Override
     public boolean mouseReleased( double x, double y, int button )
     {
+        // Make sure release events are propagated to children
         return (getFocused() != null && getFocused().mouseReleased( x, y, button ))
             || super.mouseReleased( x, y, button );
     }

src/main/java/dan200/computercraft/client/gui/GuiTurtle.java

@@ -17,6 +17,7 @@ import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
 import net.minecraft.client.gui.ContainerScreen;
 import net.minecraft.entity.player.PlayerInventory;
 import net.minecraft.util.Identifier;
+import org.lwjgl.glfw.GLFW;
 
 public class GuiTurtle extends ContainerScreen<ContainerTurtle>
 {
@@ -116,4 +117,25 @@ public class GuiTurtle extends ContainerScreen<ContainerTurtle>
         super.render( mouseX, mouseY, partialTicks );
         drawMouseoverTooltip( mouseX, mouseY );
     }
+
+    @Override
+    public boolean keyPressed( int key, int scancode, int modifiers )
+    {
+        return (key == GLFW.GLFW_KEY_TAB && getFocused() == terminalWrapper && terminalWrapper.keyPressed( key, scancode, modifiers ))
+            || super.keyPressed( key, scancode, modifiers );
+    }
+
+    @Override
+    public boolean mouseDragged( double x, double y, int button, double deltaX, double deltaY )
+    {
+        return (getFocused() != null && getFocused().mouseDragged( x, y, button, deltaX, deltaY ))
+            || super.mouseDragged( x, y, button, deltaX, deltaY );
+    }
+
+    @Override
+    public boolean mouseReleased( double x, double y, int button )
+    {
+        return (getFocused() != null && getFocused().mouseReleased( x, y, button ))
+            || super.mouseReleased( x, y, button );
+    }
 }

src/main/java/dan200/computercraft/client/proxy/ComputerCraftProxyClient.java

@@ -12,6 +12,7 @@ import dan200.computercraft.client.gui.*;
 import dan200.computercraft.client.render.TileEntityCableRenderer;
 import dan200.computercraft.client.render.TileEntityMonitorRenderer;
 import dan200.computercraft.client.render.TileEntityTurtleRenderer;
+import dan200.computercraft.client.render.TurtleModelLoader;
 import dan200.computercraft.shared.computer.blocks.TileComputer;
 import dan200.computercraft.shared.computer.core.ClientComputer;
 import dan200.computercraft.shared.computer.inventory.ContainerViewComputer;
@@ -20,7 +21,9 @@ import dan200.computercraft.shared.peripheral.modem.wired.TileCable;
 import dan200.computercraft.shared.peripheral.monitor.TileMonitor;
 import dan200.computercraft.shared.turtle.blocks.TileTurtle;
 import dan200.computercraft.shared.turtle.inventory.ContainerTurtle;
+import net.fabricmc.fabric.api.client.model.ModelLoadingRegistry;
 import net.fabricmc.fabric.api.client.render.BlockEntityRendererRegistry;
+import net.fabricmc.fabric.api.event.client.ClientSpriteRegistryCallback;
 
 public final class ComputerCraftProxyClient
 {
@@ -34,6 +37,11 @@ public final class ComputerCraftProxyClient
         BlockEntityRendererRegistry.INSTANCE.register( TileTurtle.class, new TileEntityTurtleRenderer() );
 
         ClientRegistry.onItemColours();
+        ClientSpriteRegistryCallback.registerBlockAtlas( ClientRegistry::onTextureStitchEvent );
+        ModelLoadingRegistry.INSTANCE.registerAppender( ClientRegistry::onModelBakeEvent );
+        ModelLoadingRegistry.INSTANCE.registerResourceProvider( loader -> ( name, context ) ->
+            TurtleModelLoader.INSTANCE.accepts( name ) ? TurtleModelLoader.INSTANCE.loadModel( name ) : null
+        );
     }
 
     private static void registerContainers()

src/main/java/dan200/computercraft/shared/mixin/MixinBlock.java

@@ -0,0 +1,34 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.mixin;
+
+import dan200.computercraft.shared.util.DropConsumer;
+import net.minecraft.block.Block;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.World;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+/**
+ * @see Block#dropStack(World, BlockPos, ItemStack)
+ */
+@Mixin( Block.class )
+public class MixinBlock
+{
+    @Inject(
+        method = "dropStack",
+        at = @At( value = "INVOKE", target = "Lnet/minecraft/world/World;spawnEntity(Lnet/minecraft/entity/Entity;)Z" ),
+        cancellable = true
+    )
+    private static void dropStack( World world, BlockPos pos, ItemStack stack, CallbackInfo callbackInfo )
+    {
+        if( DropConsumer.onHarvestDrops( world, pos, stack ) ) callbackInfo.cancel();
+    }
+}

src/main/java/dan200/computercraft/shared/mixin/MixinEntity.java

@@ -0,0 +1,33 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.mixin;
+
+import dan200.computercraft.shared.util.DropConsumer;
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.ItemEntity;
+import net.minecraft.item.ItemStack;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+/**
+ * @see Entity#dropStack(ItemStack, float)
+ */
+@Mixin( Entity.class )
+public class MixinEntity
+{
+    @Inject(
+        method = "dropStack(Lnet/minecraft/item/ItemStack;F)Lnet/minecraft/entity/ItemEntity;",
+        at = @At( value = "INVOKE", target = "Lnet/minecraft/world/World;spawnEntity(Lnet/minecraft/entity/Entity;)Z" ),
+        cancellable = true
+    )
+    public void dropStack( ItemStack stack, float height, CallbackInfoReturnable<ItemEntity> callbackInfo )
+    {
+        if( DropConsumer.onEntityLivingDrops( (Entity) (Object) this, stack ) ) callbackInfo.setReturnValue( null );
+    }
+}

src/main/java/dan200/computercraft/shared/mixin/MixinServerWorld.java

@@ -0,0 +1,28 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2019. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+
+package dan200.computercraft.shared.mixin;
+
+import dan200.computercraft.shared.util.DropConsumer;
+import net.minecraft.entity.Entity;
+import net.minecraft.server.world.ServerWorld;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+/**
+ * @see ServerWorld#spawnEntity(Entity)
+ */
+@Mixin( ServerWorld.class )
+public class MixinServerWorld
+{
+    @Inject( method = "spawnEntity", at = @At( "HEAD" ), cancellable = true )
+    public void spawnEntity( Entity entity, CallbackInfoReturnable<Boolean> callbackInfo )
+    {
+        if( DropConsumer.onEntitySpawn( entity ) ) callbackInfo.setReturnValue( false );
+    }
+}

src/main/java/dan200/computercraft/shared/turtle/core/TurtlePlaceCommand.java

@@ -286,9 +286,8 @@ public class TurtlePlaceCommand implements ITurtleCommand
     private static boolean canDeployOnBlock( @Nonnull ItemPlacementContext context, ITurtleAccess turtle, TurtlePlayer player, BlockPos position, Direction side, boolean allowReplaceable, String[] outErrorMessage )
     {
         World world = turtle.getWorld();
-        if( World.isValid( position ) &&
+        if( !World.isValid( position ) || world.isAir( position ) ||
-            !world.isAir( position ) &&
+            (context.getItemStack().getItem() instanceof BlockItem && WorldUtil.isLiquidBlock( world, position )) )
-            !(context.getItemStack().getItem() instanceof BlockItem && WorldUtil.isLiquidBlock( world, position )) )
         {
             return false;
         }

src/main/java/dan200/computercraft/shared/turtle/upgrades/TurtleTool.java

@@ -21,6 +21,7 @@ import dan200.computercraft.shared.util.ItemStorage;
 import dan200.computercraft.shared.util.WorldUtil;
 import net.fabricmc.api.EnvType;
 import net.fabricmc.api.Environment;
+import net.fabricmc.fabric.api.event.player.AttackEntityCallback;
 import net.minecraft.block.Block;
 import net.minecraft.block.BlockState;
 import net.minecraft.block.Blocks;
@@ -33,6 +34,8 @@ import net.minecraft.entity.damage.DamageSource;
 import net.minecraft.entity.decoration.ArmorStandEntity;
 import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
+import net.minecraft.util.ActionResult;
+import net.minecraft.util.Hand;
 import net.minecraft.util.Identifier;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.Direction;
@@ -99,8 +102,7 @@ public class TurtleTool extends AbstractTurtleUpgrade
         Block block = state.getBlock();
         return !state.isAir()
             && block != Blocks.BEDROCK
-            && state.getHardness( world, pos ) > 0
+            && state.calcBlockBreakingDelta( player, world, pos ) > 0;
-            /*&& block.canEntityDestroy( state, world, pos, player )*/;
     }
 
     protected float getDamageMultiplier()
@@ -128,12 +130,11 @@ public class TurtleTool extends AbstractTurtleUpgrade
             Entity hitEntity = hit.getKey();
 
             // Fire several events to ensure we have permissions.
-            /*
+            if( AttackEntityCallback.EVENT.invoker().interact( turtlePlayer, world, Hand.MAIN, hitEntity, null ) == ActionResult.FAIL
-            if( MinecraftForge.EVENT_BUS.post( new AttackEntityEvent( turtlePlayer, hitEntity ) ) || !hitEntity.canBeAttackedWithItem() )
+                || !hitEntity.canPlayerAttack() )
             {
                 return TurtleCommandResult.failure( "Nothing to attack here" );
             }
-            */
 
             TurtleAttackEvent attackEvent = new TurtleAttackEvent( turtle, turtlePlayer, hitEntity, this, side );
             if( TurtleEvent.post( attackEvent ) )

src/main/java/dan200/computercraft/shared/util/DropConsumer.java

@@ -7,6 +7,7 @@
 package dan200.computercraft.shared.util;
 
 import net.minecraft.entity.Entity;
+import net.minecraft.entity.ItemEntity;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.BoundingBox;
@@ -87,44 +88,40 @@ public final class DropConsumer
         if( !remaining.isEmpty() ) remainingDrops.add( remaining );
     }
 
-    /*
+    public static boolean onEntityLivingDrops( Entity entity, ItemStack stack )
-    @SubscribeEvent( priority = EventPriority.LOWEST )
-    public static void onEntityLivingDrops( LivingDropsEvent event )
     {
         // Capture any mob drops for the current entity
-        if( dropEntity != null && event.getEntity() == dropEntity.get() )
+        if( dropEntity != null && entity == dropEntity.get() )
         {
-            Collection<EntityItem> drops = event.getDrops();
+            handleDrops( stack );
-            for( EntityItem entityItem : drops ) handleDrops( entityItem.getItem() );
+            return true;
-            drops.clear();
-        }
         }
 
-    @SubscribeEvent( priority = EventPriority.LOWEST )
+        return false;
-    public static void onHarvestDrops( BlockEvent.HarvestDropsEvent event )
+    }
+
+    public static boolean onHarvestDrops( World world, BlockPos pos, ItemStack stack )
     {
         // Capture block drops for the current entity
-        if( dropWorld != null && dropWorld.get() == event.getWorld()
+        if( dropWorld != null && dropWorld.get() == world && dropPos != null && dropPos.equals( pos ) )
-            && dropPos != null && dropPos.equals( event.getPos() ) )
         {
-            for( ItemStack item : event.getDrops() )
+            handleDrops( stack );
-            {
+            return true;
-                if( event.getWorld().getRandom().nextFloat() < event.getDropChance() ) handleDrops( item );
-            }
-            event.getDrops().clear();
-        }
         }
 
-    @SubscribeEvent( priority = EventPriority.LOWEST )
+        return false;
-    public static void onEntitySpawn( EntityJoinWorldEvent event )
+    }
+
+    public static boolean onEntitySpawn( Entity entity )
     {
         // Capture any nearby item spawns
-        if( dropWorld != null && dropWorld.get() == event.getWorld() && event.getEntity() instanceof EntityItem
+        if( dropWorld != null && dropWorld.get() == entity.getEntityWorld() && entity instanceof ItemEntity
-            && dropBounds.contains( event.getEntity().getPositionVector() ) )
+            && dropBounds.contains( entity.getPos() ) )
         {
-            handleDrops( ((EntityItem) event.getEntity()).getItem() );
+            handleDrops( ((ItemEntity) entity).getStack() );
-            event.setCanceled( true );
+            return true;
         }
+
+        return false;
     }
-    */
 }

src/main/java/dan200/computercraft/shared/util/ItemStorage.java

@@ -6,6 +6,7 @@
 
 package dan200.computercraft.shared.util;
 
+import dan200.computercraft.ComputerCraft;
 import net.minecraft.inventory.Inventory;
 import net.minecraft.inventory.SidedInventory;
 import net.minecraft.item.ItemStack;
@@ -58,8 +59,8 @@ public interface ItemStorage
         }
 
         @Override
-        public @Nonnull
+        @Nonnull
-        ItemStack take( int slot, int limit, @Nonnull ItemStack filter, boolean simulate )
+        public ItemStack take( int slot, int limit, @Nonnull ItemStack filter, boolean simulate )
         {
             ItemStack existing = inventory.getInvStack( slot );
             if( existing.isEmpty() || !canExtract( slot, existing )
@@ -88,8 +89,8 @@ public interface ItemStorage
         }
 
         @Override
-        public @Nonnull
+        @Nonnull
-        ItemStack store( int slot, @Nonnull ItemStack stack, boolean simulate )
+        public ItemStack store( int slot, @Nonnull ItemStack stack, boolean simulate )
         {
             if( stack.isEmpty() || !inventory.isValidInvStack( slot, stack ) ) return stack;
 
@@ -97,7 +98,7 @@ public interface ItemStorage
             if( existing.isEmpty() )
             {
                 int limit = Math.min( stack.getMaxAmount(), inventory.getInvMaxStackAmount() );
-                if( limit <= 0 ) return ItemStack.EMPTY;
+                if( limit <= 0 ) return stack;
 
                 if( stack.getAmount() < limit )
                 {
@@ -114,8 +115,8 @@ public interface ItemStorage
             }
             else if( areStackable( stack, existing ) )
             {
-                int limit = Math.min( existing.getMaxAmount(), inventory.getInvMaxStackAmount() ) - stack.getAmount();
+                int limit = Math.min( existing.getMaxAmount(), inventory.getInvMaxStackAmount() ) - existing.getAmount();
-                if( limit <= 0 ) return ItemStack.EMPTY;
+                if( limit <= 0 ) return stack;
 
                 if( stack.getAmount() < limit )
                 {
@@ -140,7 +141,7 @@ public interface ItemStorage
             }
             else
             {
-                return ItemStack.EMPTY;
+                return stack;
             }
         }
     }
@@ -169,24 +170,23 @@ public interface ItemStorage
             return super.canExtract( slot, stack ) && inventory.canExtractInvStack( slot, stack, facing );
         }
 
+        @Nonnull
         @Override
-        public @Nonnull
+        public ItemStack take( int slot, int limit, @Nonnull ItemStack filter, boolean simulate )
-        ItemStack take( int slot, int limit, @Nonnull ItemStack filter, boolean simulate )
         {
             int[] slots = inventory.getInvAvailableSlots( facing );
             return slot >= 0 && slot < slots.length ? super.take( slots[slot], limit, filter, simulate ) : ItemStack.EMPTY;
-
         }
 
+        @Nonnull
         @Override
-        public @Nonnull
+        public ItemStack store( int slot, @Nonnull ItemStack stack, boolean simulate )
-        ItemStack store( int slot, @Nonnull ItemStack stack, boolean simulate )
         {
             int[] slots = inventory.getInvAvailableSlots( facing );
-            if( slot < 0 || slot >= slots.length ) return ItemStack.EMPTY;
+            if( slot < 0 || slot >= slots.length ) return stack;
 
             int mappedSlot = slots[slot];
-            if( !inventory.canInsertInvStack( slot, stack, facing ) ) return ItemStack.EMPTY;
+            if( !inventory.canInsertInvStack( slot, stack, facing ) ) return stack;
             return super.store( mappedSlot, stack, simulate );
         }
     }
@@ -197,7 +197,7 @@ public interface ItemStorage
         private final int start;
         private final int size;
 
-        public View( ItemStorage parent, int start, int size )
+        View( ItemStorage parent, int start, int size )
         {
             this.parent = parent;
             this.start = start;
@@ -210,19 +210,19 @@ public interface ItemStorage
             return size;
         }
 
+        @Nonnull
         @Override
-        public @Nonnull
+        public ItemStack take( int slot, int limit, @Nonnull ItemStack filter, boolean simulate )
-        ItemStack take( int slot, int limit, @Nonnull ItemStack filter, boolean simulate )
         {
             if( slot < start || slot >= start + size ) return ItemStack.EMPTY;
             return parent.take( slot - start, limit, filter, simulate );
         }
 
+        @Nonnull
         @Override
-        public @Nonnull
+        public ItemStack store( int slot, @Nonnull ItemStack stack, boolean simulate )
-        ItemStack store( int slot, @Nonnull ItemStack stack, boolean simulate )
         {
-            if( slot < start || slot >= start + size ) return ItemStack.EMPTY;
+            if( slot < start || slot >= start + size ) return stack;
             return parent.store( slot - start, stack, simulate );
         }
 

src/main/java/dan200/computercraft/shared/util/WorldUtil.java

@@ -8,9 +8,7 @@ package dan200.computercraft.shared.util;
 
 import com.google.common.base.Predicate;
 import net.minecraft.block.BlockState;
-import net.minecraft.entity.Entity;
+import net.minecraft.entity.*;
-import net.minecraft.entity.ItemEntity;
-import net.minecraft.entity.LivingEntity;
 import net.minecraft.entity.player.PlayerEntity;
 import net.minecraft.item.ItemStack;
 import net.minecraft.util.hit.HitResult;
@@ -31,6 +29,21 @@ public final class WorldUtil
     @SuppressWarnings( "Guava" )
     private static final Predicate<Entity> CAN_COLLIDE = x -> x != null && x.isAlive() && x.collides();
 
+    private static final Entity ENTITY = new ItemEntity( EntityType.ITEM, null )
+    {
+        @Override
+        public EntitySize getSize( EntityPose pos )
+        {
+            return EntitySize.constant( 0, 0 );
+        }
+    };
+
+    static
+    {
+        ENTITY.noClip = true;
+        ENTITY.refreshSize();
+    }
+
     public static boolean isLiquidBlock( World world, BlockPos pos )
     {
         if( !World.isValid( pos ) ) return false;
@@ -51,7 +64,8 @@ public final class WorldUtil
         Vec3d vecEnd = vecStart.add( vecDir.x * distance, vecDir.y * distance, vecDir.z * distance );
 
         // Raycast for blocks
-        HitResult result = world.rayTrace( new RayTraceContext( vecStart, vecEnd, RayTraceContext.ShapeType.OUTLINE, RayTraceContext.FluidHandling.NONE, null ) );
+        ENTITY.setPosition( vecStart.x, vecStart.y, vecStart.z );
+        HitResult result = world.rayTrace( new RayTraceContext( vecStart, vecEnd, RayTraceContext.ShapeType.OUTLINE, RayTraceContext.FluidHandling.NONE, ENTITY ) );
         if( result != null && result.getType() == HitResult.Type.BLOCK )
         {
             distance = vecStart.distanceTo( result.getPos() );

src/main/resources/computercraft.common.json

@@ -0,0 +1,13 @@
+{
+    "required": true,
+    "package": "dan200.computercraft.shared.mixin",
+    "compatibilityLevel": "JAVA_8",
+    "mixins": [
+        "MixinBlock",
+        "MixinEntity",
+        "MixinServerWorld"
+    ],
+    "injectors": {
+        "defaultRequire": 1
+    }
+}

src/main/resources/data/computercraft/advancements/recipes/computer_advanced.json

@@ -7,7 +7,7 @@
         "has_redstone": {
             "trigger": "minecraft:inventory_changed",
             "conditions": {
-                "items": [ { "tag": "forge:dusts/redstone" } ]
+                "items": [ { "item": "minecraft:redstone" } ]
             }
         },
         "has_the_recipe": {

src/main/resources/data/computercraft/advancements/recipes/computer_normal.json

@@ -7,7 +7,7 @@
         "has_redstone": {
             "trigger": "minecraft:inventory_changed",
             "conditions": {
-                "items": [ { "tag": "forge:dusts/redstone" } ]
+                "items": [ { "item": "minecraft:redstone" } ]
             }
         },
         "has_the_recipe": {

src/main/resources/fabric.mod.json

@@ -22,6 +22,7 @@
         "main": [ "dan200.computercraft.ComputerCraft" ]
     },
     "mixins": [
-        { "config": "computercraft.client.json", "environment": "client" }
+        { "config": "computercraft.client.json", "environment": "client" },
+        "computercraft.common.json"
     ]
 }