PaperMC/paper-server/nms-patches/net/minecraft/world/item/crafting/CraftingManager.patch

--- a/net/minecraft/world/item/crafting/CraftingManager.java
+++ b/net/minecraft/world/item/crafting/CraftingManager.java
@@ -37,11 +37,13 @@
 import net.minecraft.world.level.World;
 import org.slf4j.Logger;
 
+import it.unimi.dsi.fastutil.objects.Object2ObjectLinkedOpenHashMap; // CraftBukkit
+
 public class CraftingManager extends ResourceDataJson {
 
     private static final Gson GSON = (new GsonBuilder()).setPrettyPrinting().disableHtmlEscaping().create();
     private static final Logger LOGGER = LogUtils.getLogger();
-    public Map<Recipes<?>, Map<MinecraftKey, RecipeHolder<?>>> recipes = ImmutableMap.of();
+    public Map<Recipes<?>, Object2ObjectLinkedOpenHashMap<MinecraftKey, RecipeHolder<?>>> recipes = ImmutableMap.of(); // CraftBukkit
     private Map<MinecraftKey, RecipeHolder<?>> byName = ImmutableMap.of();
     private boolean hasErrors;
 
@@ -51,7 +53,12 @@
 
     protected void apply(Map<MinecraftKey, JsonElement> map, IResourceManager iresourcemanager, GameProfilerFiller gameprofilerfiller) {
         this.hasErrors = false;
-        Map<Recipes<?>, Builder<MinecraftKey, RecipeHolder<?>>> map1 = Maps.newHashMap();
+        // CraftBukkit start - SPIGOT-5667 make sure all types are populated and mutable
+        Map<Recipes<?>, Object2ObjectLinkedOpenHashMap<MinecraftKey, RecipeHolder<?>>> map1 = Maps.newHashMap();
+        for (Recipes<?> recipeType : BuiltInRegistries.RECIPE_TYPE) {
+            map1.put(recipeType, new Object2ObjectLinkedOpenHashMap<>());
+        }
+        // CraftBukkit end
         Builder<MinecraftKey, RecipeHolder<?>> builder = ImmutableMap.builder();
         Iterator iterator = map.entrySet().iterator();
 
@@ -62,8 +69,10 @@
             try {
                 RecipeHolder<?> recipeholder = fromJson(minecraftkey, ChatDeserializer.convertToJsonObject((JsonElement) entry.getValue(), "top element"));
 
-                ((Builder) map1.computeIfAbsent(recipeholder.value().getType(), (recipes) -> {
-                    return ImmutableMap.builder();
+                // CraftBukkit start
+                (map1.computeIfAbsent(recipeholder.value().getType(), (recipes) -> {
+                    return new Object2ObjectLinkedOpenHashMap<>();
+                    // CraftBukkit end
                 })).put(minecraftkey, recipeholder);
                 builder.put(minecraftkey, recipeholder);
             } catch (IllegalArgumentException | JsonParseException jsonparseexception) {
@@ -72,20 +81,37 @@
         }
 
         this.recipes = (Map) map1.entrySet().stream().collect(ImmutableMap.toImmutableMap(Entry::getKey, (entry1) -> {
-            return ((Builder) entry1.getValue()).build();
+            return (entry1.getValue()); // CraftBukkit
         }));
-        this.byName = builder.build();
+        this.byName = Maps.newHashMap(builder.build()); // CraftBukkit
         CraftingManager.LOGGER.info("Loaded {} recipes", map1.size());
     }
 
+    // CraftBukkit start
+    public void addRecipe(RecipeHolder<?> irecipe) {
+        Object2ObjectLinkedOpenHashMap<MinecraftKey, RecipeHolder<?>> map = this.recipes.get(irecipe.value().getType()); // CraftBukkit
+
+        if (byName.containsKey(irecipe.id()) || map.containsKey(irecipe.id())) {
+            throw new IllegalStateException("Duplicate recipe ignored with ID " + irecipe.id());
+        } else {
+            map.putAndMoveToFirst(irecipe.id(), irecipe); // CraftBukkit - SPIGOT-4638: last recipe gets priority
+            byName.put(irecipe.id(), irecipe);
+        }
+    }
+    // CraftBukkit end
+
     public boolean hadErrorsLoading() {
         return this.hasErrors;
     }
 
     public <C extends IInventory, T extends IRecipe<C>> Optional<RecipeHolder<T>> getRecipeFor(Recipes<T> recipes, C c0, World world) {
-        return this.byType(recipes).values().stream().filter((recipeholder) -> {
+        // CraftBukkit start
+        Optional<RecipeHolder<T>> recipe = this.byType(recipes).values().stream().filter((recipeholder) -> {
             return recipeholder.value().matches(c0, world);
         }).findFirst();
+        c0.setCurrentRecipe(recipe.orElse(null)); // CraftBukkit - Clear recipe when no recipe is found
+        return recipe;
+        // CraftBukkit end
     }
 
     public <C extends IInventory, T extends IRecipe<C>> Optional<Pair<MinecraftKey, RecipeHolder<T>>> getRecipeFor(Recipes<T> recipes, C c0, World world, @Nullable MinecraftKey minecraftkey) {
@@ -119,7 +145,7 @@
     }
 
     private <C extends IInventory, T extends IRecipe<C>> Map<MinecraftKey, RecipeHolder<T>> byType(Recipes<T> recipes) {
-        return (Map) this.recipes.getOrDefault(recipes, Collections.emptyMap());
+        return (Map) this.recipes.getOrDefault(recipes, new Object2ObjectLinkedOpenHashMap<>()); // CraftBukkit
     }
 
     public <C extends IInventory, T extends IRecipe<C>> NonNullList<ItemStack> getRemainingItemsFor(Recipes<T> recipes, C c0, World world) {
@@ -166,12 +192,12 @@
 
     public void replaceRecipes(Iterable<RecipeHolder<?>> iterable) {
         this.hasErrors = false;
-        Map<Recipes<?>, Map<MinecraftKey, RecipeHolder<?>>> map = Maps.newHashMap();
+        Map<Recipes<?>, Object2ObjectLinkedOpenHashMap<MinecraftKey, RecipeHolder<?>>> map = Maps.newHashMap(); // CraftBukkit
         Builder<MinecraftKey, RecipeHolder<?>> builder = ImmutableMap.builder();
 
         iterable.forEach((recipeholder) -> {
             Map<MinecraftKey, RecipeHolder<?>> map1 = (Map) map.computeIfAbsent(recipeholder.value().getType(), (recipes) -> {
-                return Maps.newHashMap();
+                return new Object2ObjectLinkedOpenHashMap<>(); // CraftBukkit
             });
             MinecraftKey minecraftkey = recipeholder.id();
             RecipeHolder<?> recipeholder1 = (RecipeHolder) map1.put(minecraftkey, recipeholder);
@@ -182,9 +208,29 @@
             }
         });
         this.recipes = ImmutableMap.copyOf(map);
-        this.byName = builder.build();
+        this.byName = Maps.newHashMap(builder.build()); // CraftBukkit
+    }
+
+    // CraftBukkit start
+    public boolean removeRecipe(MinecraftKey mcKey) {
+        for (Object2ObjectLinkedOpenHashMap<MinecraftKey, RecipeHolder<?>> recipes : recipes.values()) {
+            recipes.remove(mcKey);
+        }
+
+        return byName.remove(mcKey) != null;
     }
 
+    public void clearRecipes() {
+        this.recipes = Maps.newHashMap();
+
+        for (Recipes<?> recipeType : BuiltInRegistries.RECIPE_TYPE) {
+            this.recipes.put(recipeType, new Object2ObjectLinkedOpenHashMap<>());
+        }
+
+        this.byName = Maps.newHashMap();
+    }
+    // CraftBukkit end
+
     public static <C extends IInventory, T extends IRecipe<C>> CraftingManager.a<C, T> createCheck(final Recipes<T> recipes) {
         return new CraftingManager.a<C, T>() {
             @Nullable