Neo 1.20.1 should now compile with Kilt. Just need to fix injects.

buildSrc/src/main/kotlin/xyz/bluspring/kilt/gradle/AccessTransformerRemapper.kt

@@ -120,6 +120,9 @@ class AccessTransformerRemapper {
             }
         }
 
+        // Custom widener values for Kilt
+        widener += "transitive-accessible class net/minecraft/world/item/CreativeModeTab\$ItemDisplayBuilder"
+
         if (!output.exists())
             output.createNewFile()
 

src/main/java/xyz/bluspring/kilt/forgeinjects/client/renderer/texture/SpriteContentsInject.java

@@ -0,0 +1,44 @@
+package xyz.bluspring.kilt.forgeinjects.client.renderer.texture;
+
+import com.mojang.blaze3d.platform.NativeImage;
+import net.minecraft.client.renderer.texture.SpriteContents;
+import net.minecraft.client.resources.metadata.animation.AnimationMetadataSection;
+import net.minecraft.client.resources.metadata.animation.FrameSize;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraftforge.client.textures.ForgeTextureMetadata;
+import org.jetbrains.annotations.Nullable;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import xyz.bluspring.kilt.helpers.mixin.CreateInitializer;
+import xyz.bluspring.kilt.injections.client.renderer.texture.SpriteContentsInjection;
+
+@Mixin(SpriteContents.class)
+public class SpriteContentsInject implements SpriteContentsInjection {
+    @Shadow @Final private NativeImage originalImage;
+    @Nullable
+    public ForgeTextureMetadata forgeMeta;
+
+    public SpriteContentsInject(ResourceLocation name, FrameSize frameSize, NativeImage originalImage, AnimationMetadataSection metadata) {}
+
+    @CreateInitializer
+    public SpriteContentsInject(ResourceLocation name, FrameSize frameSize, NativeImage originalImage, AnimationMetadataSection metadata, @Nullable ForgeTextureMetadata forgeMeta) {
+        this.forgeMeta = forgeMeta;
+    }
+
+
+    @Override
+    public NativeImage getOriginalImage() {
+        return this.originalImage;
+    }
+
+    @Override
+    public ForgeTextureMetadata kilt$getForgeMeta() {
+        return this.forgeMeta;
+    }
+
+    @Override
+    public void kilt$setForgeMeta(ForgeTextureMetadata metadata) {
+        this.forgeMeta = metadata;
+    }
+}

src/main/java/xyz/bluspring/kilt/forgeinjects/core/RegistrySetBuilderInject.java

@@ -0,0 +1,21 @@
+package xyz.bluspring.kilt.forgeinjects.core;
+
+import net.minecraft.core.Registry;
+import net.minecraft.core.RegistrySetBuilder;
+import net.minecraft.resources.ResourceKey;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import xyz.bluspring.kilt.injections.core.RegistrySetBuilderInjection;
+
+import java.util.List;
+
+@Mixin(RegistrySetBuilder.class)
+public class RegistrySetBuilderInject implements RegistrySetBuilderInjection {
+    @Shadow @Final public List<RegistrySetBuilder.RegistryStub<?>> entries;
+
+    @Override
+    public List<? extends ResourceKey<? extends Registry<?>>> getEntryKeys() {
+        return this.entries.stream().map(RegistrySetBuilder.RegistryStub::key).toList();
+    }
+}

src/main/java/xyz/bluspring/kilt/forgeinjects/data/DataGeneratorInject.java

@@ -1,43 +1,57 @@
 package xyz.bluspring.kilt.forgeinjects.data;
 
-import net.minecraft.WorldVersion;
 import net.minecraft.data.DataGenerator;
 import net.minecraft.data.DataProvider;
-import org.apache.commons.compress.utils.Lists;
-import org.objectweb.asm.Opcodes;
+import net.minecraft.data.PackOutput;
 import org.spongepowered.asm.mixin.Final;
 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.ModifyVariable;
-import org.spongepowered.asm.mixin.injection.Redirect;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import org.spongepowered.asm.mixin.Unique;
 import xyz.bluspring.kilt.injections.data.DataGeneratorInjection;
-import xyz.bluspring.kilt.mixin.DataGeneratorAccessor;
 
 import java.nio.file.Path;
-import java.util.Collection;
-import java.util.List;
+import java.util.Collections;
+import java.util.Map;
+import java.util.Set;
 
 @Mixin(DataGenerator.class)
 public class DataGeneratorInject implements DataGeneratorInjection {
-    @Shadow @Final private Collection<Path> inputFolders;
+    @Shadow @Final private Map<String, DataProvider> providersToRun;
+    @Shadow @Final private PackOutput vanillaPackOutput;
+    @Shadow @Final private Path rootOutputFolder;
+    @Shadow @Final private Set<String> allProviderIds;
+    @Unique private final Map<String, DataProvider> providersView = Collections.unmodifiableMap(this.providersToRun);
 
-    @Shadow @Final private List<DataProvider> allProviders;
+    @Override
+    public Map<String, DataProvider> getProvidersView() {
+        return this.providersView;
+    }
 
-    @Redirect(at = @At(value = "FIELD", target = "Lnet/minecraft/data/DataGenerator;inputFolders:Ljava/util/Collection;", opcode = Opcodes.PUTFIELD), method = "<init>")
-    public void kilt$makeInputsMutable(DataGenerator instance, Collection<Path> value) {
-        ((DataGeneratorAccessor) instance).setInputFolders(Lists.newArrayList(value.iterator()));
+    @Override
+    public PackOutput getPackOutput() {
+        return this.vanillaPackOutput;
     }
 
     @Override
-    public List<DataProvider> getProviders() {
-        return this.allProviders;
+    public PackOutput getPackOutput(String path) {
+        return new PackOutput(this.rootOutputFolder.resolve(path));
     }
 
     @Override
-    public void addInput(Path value) {
-        inputFolders.add(value);
+    public <T extends DataProvider> T addProvider(boolean run, DataProvider.Factory<T> factory) {
+        return addProvider(run, factory.create(this.vanillaPackOutput));
+    }
+
+    @Override
+    public <T extends DataProvider> T addProvider(boolean run, T provider) {
+        var id = provider.getName();
+
+        if (!this.allProviderIds.add(id))
+            throw new IllegalStateException("Duplicate provider: " + id);
+
+        if (run)
+            this.providersToRun.put(id, provider);
+
+        return provider;
     }
 }

src/main/java/xyz/bluspring/kilt/forgeinjects/data/recipes/RecipeProviderInject.java

@@ -1,162 +1,24 @@
 package xyz.bluspring.kilt.forgeinjects.data.recipes;
 
+import com.google.gson.JsonObject;
+import net.minecraft.data.CachedOutput;
+import net.minecraft.data.DataProvider;
+import net.minecraft.data.PackOutput;
 import net.minecraft.data.recipes.FinishedRecipe;
 import net.minecraft.data.recipes.RecipeProvider;
-import net.minecraft.data.recipes.ShapedRecipeBuilder;
-import net.minecraft.data.recipes.ShapelessRecipeBuilder;
-import net.minecraft.resources.ResourceLocation;
-import net.minecraft.tags.TagKey;
-import net.minecraft.world.item.Item;
-import net.minecraft.world.item.ItemStack;
-import net.minecraft.world.item.Items;
-import net.minecraft.world.item.crafting.Ingredient;
-import net.minecraft.world.level.ItemLike;
-import net.minecraft.world.level.block.Blocks;
-import net.minecraftforge.common.Tags;
-import net.minecraftforge.registries.ForgeRegistries;
 import org.jetbrains.annotations.Nullable;
 import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.injection.*;
+import org.spongepowered.asm.mixin.Shadow;
+import xyz.bluspring.kilt.injections.data.recipes.RecipeProviderInjection;
 
-import java.lang.reflect.Field;
-import java.util.*;
-import java.util.function.Consumer;
+import java.util.concurrent.CompletableFuture;
 
 @Mixin(RecipeProvider.class)
-public class RecipeProviderInject {
-    private static final Map<Item, TagKey<Item>> replacements = new HashMap<>();
-    private static final Set<ResourceLocation> excludes = new HashSet<>();
+public class RecipeProviderInject implements RecipeProviderInjection {
+    @Shadow public PackOutput.PathProvider advancementPathProvider;
 
-    private static void exclude(ItemLike item)
-    {
-        excludes.add(ForgeRegistries.ITEMS.getKey(item.asItem()));
-    }
-
-    private static void replace(ItemLike item, TagKey<Item> tag)
-    {
-        replacements.put(item.asItem(), tag);
-    }
-
-    @Nullable
-    private static FinishedRecipe enhance(FinishedRecipe vanilla)
-    {
-        if (vanilla instanceof ShapelessRecipeBuilder.Result shapeless)
-            return enhance(shapeless);
-        if (vanilla instanceof ShapedRecipeBuilder.Result shaped)
-            return enhance(shaped);
-        return null;
-    }
-
-    @Nullable
-    private static FinishedRecipe enhance(ShapelessRecipeBuilder.Result vanilla)
-    {
-        List<Ingredient> ingredients = getField(ShapelessRecipeBuilder.Result.class, vanilla, 4);
-        boolean modified = false;
-        for (int x = 0; x < ingredients.size(); x++)
-        {
-            Ingredient ing = enhance(vanilla.getId(), ingredients.get(x));
-            if (ing != null)
-            {
-                ingredients.set(x, ing);
-                modified = true;
-            }
-        }
-        return modified ? vanilla : null;
-    }
-
-    @Nullable
-    private static FinishedRecipe enhance(ShapedRecipeBuilder.Result vanilla)
-    {
-        Map<Character, Ingredient> ingredients = getField(ShapedRecipeBuilder.Result.class, vanilla, 5);
-        boolean modified = false;
-        for (Character x : ingredients.keySet())
-        {
-            Ingredient ing = enhance(vanilla.getId(), ingredients.get(x));
-            if (ing != null)
-            {
-                ingredients.put(x, ing);
-                modified = true;
-            }
-        }
-        return modified ? vanilla : null;
-    }
-
-    @Nullable
-    private static Ingredient enhance(ResourceLocation name, Ingredient vanilla)
-    {
-        if (excludes.contains(name))
-            return null;
-
-        boolean modified = false;
-        List<Ingredient.Value> items = new ArrayList<>();
-        Ingredient.Value[] vanillaItems = getField(Ingredient.class, vanilla, 2); //This will probably crash between versions, if null fix index
-        for (Ingredient.Value entry : vanillaItems)
-        {
-            if (entry instanceof Ingredient.ItemValue)
-            {
-                ItemStack stack = entry.getItems().stream().findFirst().orElse(ItemStack.EMPTY);
-                TagKey<Item> replacement = replacements.get(stack.getItem());
-                if (replacement != null)
-                {
-                    items.add(new Ingredient.TagValue(replacement));
-                    modified = true;
-                } else
-                    items.add(entry);
-            } else
-                items.add(entry);
-        }
-        return modified ? Ingredient.fromValues(items.stream()) : null;
-    }
-
-    @SuppressWarnings("unchecked")
-    private static <T, R> R getField(Class<T> clz, T inst, int index)
-    {
-        Field fld = clz.getDeclaredFields()[index];
-        fld.setAccessible(true);
-        try
-        {
-            return (R) fld.get(inst);
-        } catch (IllegalArgumentException | IllegalAccessException e)
-        {
-            throw new RuntimeException(e);
-        }
-    }
-
-    @ModifyVariable(at = @At("HEAD"), method = "buildCraftingRecipes", argsOnly = true)
-    private static Consumer<FinishedRecipe> kilt$replaceRecipes(Consumer<FinishedRecipe> consumer) {
-        replace(Items.STICK, Tags.Items.RODS_WOODEN);
-        replace(Items.GOLD_INGOT, Tags.Items.INGOTS_GOLD);
-        replace(Items.IRON_INGOT, Tags.Items.INGOTS_IRON);
-        replace(Items.NETHERITE_INGOT, Tags.Items.INGOTS_NETHERITE);
-        replace(Items.COPPER_INGOT, Tags.Items.INGOTS_COPPER);
-        replace(Items.AMETHYST_SHARD, Tags.Items.GEMS_AMETHYST);
-        replace(Items.DIAMOND, Tags.Items.GEMS_DIAMOND);
-        replace(Items.EMERALD, Tags.Items.GEMS_EMERALD);
-        replace(Items.CHEST, Tags.Items.CHESTS_WOODEN);
-        replace(Blocks.COBBLESTONE, Tags.Items.COBBLESTONE_NORMAL);
-        replace(Blocks.COBBLED_DEEPSLATE, Tags.Items.COBBLESTONE_DEEPSLATE);
-
-        exclude(Blocks.GOLD_BLOCK);
-        exclude(Items.GOLD_NUGGET);
-        exclude(Blocks.IRON_BLOCK);
-        exclude(Items.IRON_NUGGET);
-        exclude(Blocks.DIAMOND_BLOCK);
-        exclude(Blocks.EMERALD_BLOCK);
-        exclude(Blocks.NETHERITE_BLOCK);
-        exclude(Blocks.COPPER_BLOCK);
-        exclude(Blocks.AMETHYST_BLOCK);
-
-        exclude(Blocks.COBBLESTONE_STAIRS);
-        exclude(Blocks.COBBLESTONE_SLAB);
-        exclude(Blocks.COBBLESTONE_WALL);
-        exclude(Blocks.COBBLED_DEEPSLATE_STAIRS);
-        exclude(Blocks.COBBLED_DEEPSLATE_SLAB);
-        exclude(Blocks.COBBLED_DEEPSLATE_WALL);
-
-        return (vanilla) -> {
-            FinishedRecipe modified = enhance(vanilla);
-            if (modified != null)
-                consumer.accept(modified);
-        };
+    @Override
+    public @Nullable CompletableFuture<?> saveAdvancement(CachedOutput output, FinishedRecipe finishedRecipe, JsonObject advancementJson) {
+        return DataProvider.saveStable(output, advancementJson, this.advancementPathProvider.json(finishedRecipe.getAdvancementId()));
     }
 }

src/main/java/xyz/bluspring/kilt/forgeinjects/data/registries/VanillaRegistriesInject.java

@@ -0,0 +1,16 @@
+package xyz.bluspring.kilt.forgeinjects.data.registries;
+
+import net.minecraft.core.Registry;
+import net.minecraft.data.registries.VanillaRegistries;
+import net.minecraft.resources.ResourceKey;
+import org.spongepowered.asm.mixin.Mixin;
+import xyz.bluspring.kilt.helpers.mixin.CreateStatic;
+import xyz.bluspring.kilt.injections.data.registries.VanillaRegistriesInjection;
+
+import java.util.List;
+
+@Mixin(VanillaRegistries.class)
+public class VanillaRegistriesInject {
+    @CreateStatic
+    private static final List<? extends ResourceKey<? extends Registry<?>>> DATAPACK_REGISTRY_KEYS = VanillaRegistriesInjection.DATAPACK_REGISTRY_KEYS;
+}

src/main/java/xyz/bluspring/kilt/forgeinjects/data/tags/TagsProviderInject.java

@@ -2,7 +2,9 @@
 
 import net.minecraft.core.Registry;
 import net.minecraft.data.DataGenerator;
+import net.minecraft.data.PackOutput;
 import net.minecraft.data.tags.TagsProvider;
+import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.server.packs.PackType;
 import net.minecraft.tags.TagBuilder;
@@ -23,15 +25,15 @@
 
 @Mixin(TagsProvider.class)
 public abstract class TagsProviderInject<T> implements TagsProviderInjection {
-    @Shadow @Final protected Registry<T> registry;
-    @Shadow @Final protected DataGenerator.PathProvider pathProvider;
+    @Shadow @Final
+    protected ResourceKey<? extends Registry<T>> registryKey;
+    @Shadow @Final
+    protected PackOutput.PathProvider pathProvider;
+
     protected String modId = "vanilla";
     protected ExistingFileHelper existingFileHelper = null;
-    @Unique
-    private final ExistingFileHelper.IResourceType resourceType = new ExistingFileHelper.ResourceType(PackType.SERVER_DATA, ".json", TagManager.getTagDir(this.registry.key()));
-
-    @Unique
-    private final ExistingFileHelper.IResourceType elementResourceType = new ExistingFileHelper.ResourceType(PackType.SERVER_DATA, ".json", ForgeHooks.prefixNamespace(this.registry.key().location()));
+    @Unique private final ExistingFileHelper.IResourceType resourceType = new ExistingFileHelper.ResourceType(PackType.SERVER_DATA, ".json", TagManager.getTagDir(this.registryKey));
+    @Unique private final ExistingFileHelper.IResourceType elementResourceType = new ExistingFileHelper.ResourceType(PackType.SERVER_DATA, ".json", ForgeHooks.prefixNamespace(this.registryKey.location()));
 
     @CreateInitializer
     protected TagsProviderInject(DataGenerator dataGenerator, Registry<T> registry, String modId, @Nullable ExistingFileHelper existingFileHelper) {
@@ -58,7 +60,7 @@ protected Path getPath(ResourceLocation id) {
     }
 
     @Mixin(TagsProvider.TagAppender.class)
-    public static class TagAppenderInject<T> implements IForgeTagAppender<T> {
+    public static class TagAppenderInject<T> implements IForgeTagAppender<T>, TagAppenderInjection {
         @Shadow @Final private TagBuilder builder;
         @Unique
         private String modId;