Optionally add a milk fluid to the vanilla bucket (#7294)

Fixes the previous broken code that was supposed to make mod registered milk returned by the vanilla bucket by allowing mods to enable a milk fluid.

src/main/java/net/minecraftforge/common/ForgeMod.java

@@ -24,13 +24,19 @@ import net.minecraft.command.arguments.ArgumentTypes;
 import net.minecraft.command.arguments.IArgumentSerializer;
 import net.minecraft.entity.ai.attributes.Attribute;
 import net.minecraft.entity.ai.attributes.RangedAttribute;
+import net.minecraft.fluid.Fluid;
+import net.minecraft.item.Items;
 import net.minecraft.util.SoundEvent;
 import net.minecraft.world.storage.IServerConfiguration;
 import net.minecraft.world.storage.SaveFormat;
 import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.client.ForgeHooksClient;
+import net.minecraftforge.common.data.ExistingFileHelper;
+import net.minecraftforge.common.data.ForgeFluidTagsProvider;
 import net.minecraftforge.eventbus.api.IEventBus;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
+import net.minecraftforge.fluids.FluidAttributes;
+import net.minecraftforge.fluids.ForgeFlowingFluid;
 import net.minecraftforge.fml.*;
 import net.minecraftforge.fml.config.ModConfig;
 import net.minecraftforge.fml.event.lifecycle.*;
@@ -41,6 +47,8 @@ import net.minecraftforge.fml.loading.progress.StartupMessageManager;
 import net.minecraftforge.registries.DeferredRegister;
 import net.minecraftforge.server.command.EnumArgument;
 import net.minecraftforge.server.command.ModIdArgument;
+import net.minecraftforge.registries.ForgeRegistries;
+import net.minecraftforge.registries.IForgeRegistry;
 import net.minecraftforge.versions.forge.ForgeVersion;
 import net.minecraftforge.versions.mcp.MCPVersion;
 
@@ -98,12 +106,24 @@ public class ForgeMod implements WorldPersistenceHooks.WorldPersistenceHook
 
     public static final RegistryObject<Attribute> REACH_DISTANCE = ATTRIBUTES.register("reach_distance", () -> new RangedAttribute("generic.reachDistance", 5.0D, 0.0D, 1024.0D).setShouldWatch(true));
 
+    private static boolean enableMilkFluid = false;
+    public static final RegistryObject<Fluid> MILK = RegistryObject.of(new ResourceLocation("milk"), ForgeRegistries.FLUIDS);
+    public static final RegistryObject<Fluid> FLOWING_MILK = RegistryObject.of(new ResourceLocation("flowing_milk"), ForgeRegistries.FLUIDS);
+
     private static ForgeMod INSTANCE;
     public static ForgeMod getInstance()
     {
         return INSTANCE;
     }
 
+    /**
+     * Run this method during mod constructor to enable milk and add it to the Minecraft milk bucket
+     */
+    public static void enableMilkFluid()
+    {
+        enableMilkFluid = true;
+    }
+
     public ForgeMod()
     {
         LOGGER.info(FORGEMOD,"Forge mod loading, version {}, for MC {} with MCP {}", ForgeVersion.getVersion(), MCPVersion.getMCVersion(), MCPVersion.getMCPVersion());
@@ -120,6 +140,7 @@ public class ForgeMod implements WorldPersistenceHooks.WorldPersistenceHook
         modEventBus.addListener(this::preInit);
         modEventBus.addListener(this::gatherData);
         modEventBus.addListener(this::loadComplete);
+        modEventBus.addGenericListener(Fluid.class, this::registerFluids);
         modEventBus.register(this);
         ATTRIBUTES.register(modEventBus);
         MinecraftForge.EVENT_BUS.addListener(this::serverStopping);
@@ -205,9 +226,11 @@ public class ForgeMod implements WorldPersistenceHooks.WorldPersistenceHook
 
         if (event.includeServer())
         {
-            ForgeBlockTagsProvider blockTags = new ForgeBlockTagsProvider(gen, event.getExistingFileHelper());
+            ExistingFileHelper existingFileHelper = event.getExistingFileHelper();
+            ForgeBlockTagsProvider blockTags = new ForgeBlockTagsProvider(gen, existingFileHelper);
             gen.addProvider(blockTags);
-            gen.addProvider(new ForgeItemTagsProvider(gen, blockTags, event.getExistingFileHelper()));
+            gen.addProvider(new ForgeItemTagsProvider(gen, blockTags, existingFileHelper));
+            gen.addProvider(new ForgeFluidTagsProvider(gen, existingFileHelper));
             gen.addProvider(new ForgeRecipeProvider(gen));
             gen.addProvider(new ForgeLootTableProvider(gen));
         }
@@ -232,6 +255,20 @@ public class ForgeMod implements WorldPersistenceHooks.WorldPersistenceHook
         }
     }
 
+    // done in an event instead of deferred to only enable if a mod requests it
+    public void registerFluids(RegistryEvent.Register<Fluid> event)
+    {
+        if (enableMilkFluid)
+        {
+            // set up attributes
+            FluidAttributes.Builder attributesBuilder = FluidAttributes.builder(new ResourceLocation("forge", "block/milk_still"), new ResourceLocation("forge", "block/milk_flowing")).density(1024).viscosity(1024);
+            ForgeFlowingFluid.Properties properties = new ForgeFlowingFluid.Properties(MILK, FLOWING_MILK, attributesBuilder).bucket(() -> Items.MILK_BUCKET);
+            // register fluids
+            event.getRegistry().register(new ForgeFlowingFluid.Source(properties).setRegistryName(MILK.getId()));
+            event.getRegistry().register(new ForgeFlowingFluid.Flowing(properties).setRegistryName(FLOWING_MILK.getId()));
+        }
+    }
+
     @SubscribeEvent //ModBus, can't use addListener due to nested genetics.
     public void registerRecipeSerialziers(RegistryEvent.Register<IRecipeSerializer<?>> event)
     {

src/main/java/net/minecraftforge/common/Tags.java

@@ -20,9 +20,11 @@
 package net.minecraftforge.common;
 
 import net.minecraft.block.Block;
+import net.minecraft.fluid.Fluid;
 import net.minecraft.item.DyeColor;
 import net.minecraft.item.Item;
 import net.minecraft.tags.BlockTags;
+import net.minecraft.tags.FluidTags;
 import net.minecraft.tags.ItemTags;
 import net.minecraft.util.ResourceLocation;
 import net.minecraft.tags.ITag.INamedTag;
@@ -33,6 +35,7 @@ public class Tags
     {
         Blocks.init();
         Items.init();
+        Fluids.init();
     }
 
     public static class Blocks
@@ -287,6 +290,18 @@ public class Tags
         }
     }
 
+    public static class Fluids
+    {
+        private static void init() {}
+
+        public static final IOptionalNamedTag<Fluid> MILK = tag("milk");
+
+        private static IOptionalNamedTag<Fluid> tag(String name)
+        {
+            return FluidTags.createOptional(new ResourceLocation("forge", name));
+        }
+    }
+
     public interface IOptionalNamedTag<T> extends INamedTag<T>
     {
         /**

src/main/java/net/minecraftforge/common/data/ForgeFluidTagsProvider.java

@@ -0,0 +1,46 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2016-2020.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.common.data;
+
+import net.minecraft.data.DataGenerator;
+import net.minecraft.data.FluidTagsProvider;
+import net.minecraftforge.common.ForgeMod;
+
+import static net.minecraftforge.common.Tags.Fluids.MILK;
+
+public class ForgeFluidTagsProvider extends FluidTagsProvider
+{
+    public ForgeFluidTagsProvider(DataGenerator gen, ExistingFileHelper existingFileHelper)
+    {
+        super(gen, "forge", existingFileHelper);
+    }
+
+    @Override
+    public void registerTags()
+    {
+        getOrCreateBuilder(MILK).addOptional(ForgeMod.MILK.getId()).addOptional(ForgeMod.FLOWING_MILK.getId());
+    }
+
+    @Override
+    public String getName()
+    {
+        return "Forge Fluid Tags";
+    }
+}

src/main/java/net/minecraftforge/fluids/FluidUtil.java

@@ -643,10 +643,6 @@ public class FluidUtil
             {
                 return new ItemStack(Items.LAVA_BUCKET);
             }
-            else if (fluid.getRegistryName().equals(new ResourceLocation("milk")))
-            {
-                return new ItemStack(Items.MILK_BUCKET);
-            }
         }
 
         return fluid.getAttributes().getBucket(fluidStack);

src/main/java/net/minecraftforge/fluids/capability/wrappers/FluidBucketWrapper.java

@@ -26,6 +26,7 @@ import net.minecraft.fluid.Fluids;
 import net.minecraft.item.*;
 import net.minecraft.util.Direction;
 import net.minecraft.util.ResourceLocation;
+import net.minecraftforge.common.ForgeMod;
 import net.minecraftforge.common.capabilities.Capability;
 import net.minecraftforge.common.capabilities.ICapabilityProvider;
 import net.minecraftforge.common.util.LazyOptional;
@@ -60,7 +61,7 @@ public class FluidBucketWrapper implements IFluidHandlerItem, ICapabilityProvide
 
     public boolean canFillFluidType(FluidStack fluid)
     {
-        if (fluid.getFluid() == Fluids.WATER || fluid.getFluid() == Fluids.LAVA || fluid.getFluid().getRegistryName().equals(new ResourceLocation("milk")))
+        if (fluid.getFluid() == Fluids.WATER || fluid.getFluid() == Fluids.LAVA)
         {
             return true;
         }
@@ -75,6 +76,10 @@ public class FluidBucketWrapper implements IFluidHandlerItem, ICapabilityProvide
         {
             return new FluidStack(((BucketItem)item).getFluid(), FluidAttributes.BUCKET_VOLUME);
         }
+        else if (item instanceof MilkBucketItem && ForgeMod.MILK.isPresent())
+        {
+            return new FluidStack(ForgeMod.MILK.get(), FluidAttributes.BUCKET_VOLUME);
+        }
         else
         {
             return FluidStack.EMPTY;