SPIGOT-7867: Merchant instanceof AbstractVillager always returns false

By: Miles Holder <mwholder2005@gmail.com>

paper-server/nms-patches/net/minecraft/world/entity/npc/EntityVillagerAbstract.patch

@@ -1,6 +1,6 @@
 --- a/net/minecraft/world/entity/npc/EntityVillagerAbstract.java
 +++ b/net/minecraft/world/entity/npc/EntityVillagerAbstract.java
-@@ -40,8 +40,24 @@
+@@ -40,8 +40,22 @@
  import net.minecraft.world.phys.Vec3D;
  import org.slf4j.Logger;
  
@@ -15,17 +15,15 @@
  public abstract class EntityVillagerAbstract extends EntityAgeable implements InventoryCarrier, NPC, IMerchant {
  
 +    // CraftBukkit start
-+    private CraftMerchant craftMerchant;
-+
 +    @Override
 +    public CraftMerchant getCraftMerchant() {
-+        return (craftMerchant == null) ? craftMerchant = new CraftMerchant(this) : craftMerchant;
++        return (org.bukkit.craftbukkit.entity.CraftAbstractVillager) getBukkitEntity();
 +    }
 +    // CraftBukkit end
      private static final DataWatcherObject<Integer> DATA_UNHAPPY_COUNTER = DataWatcher.defineId(EntityVillagerAbstract.class, DataWatcherRegistry.INT);
      private static final Logger LOGGER = LogUtils.getLogger();
      public static final int VILLAGER_SLOT_OFFSET = 300;
-@@ -50,7 +66,7 @@
+@@ -50,7 +64,7 @@
      private EntityHuman tradingPlayer;
      @Nullable
      protected MerchantRecipeList offers;
@@ -34,7 +32,7 @@
  
      public EntityVillagerAbstract(EntityTypes<? extends EntityVillagerAbstract> entitytypes, World world) {
          super(entitytypes, world);
-@@ -179,7 +195,7 @@
+@@ -179,7 +193,7 @@
      public void readAdditionalSaveData(NBTTagCompound nbttagcompound) {
          super.readAdditionalSaveData(nbttagcompound);
          if (nbttagcompound.contains("Offers")) {
@@ -43,7 +41,7 @@
              Logger logger = EntityVillagerAbstract.LOGGER;
  
              Objects.requireNonNull(logger);
-@@ -246,7 +262,16 @@
+@@ -246,7 +260,16 @@
              MerchantRecipe merchantrecipe = ((VillagerTrades.IMerchantRecipeOption) arraylist.remove(this.random.nextInt(arraylist.size()))).getOffer(this, this.random);
  
              if (merchantrecipe != null) {

paper-server/src/main/java/org/bukkit/craftbukkit/entity/CraftAbstractVillager.java

@@ -1,18 +1,16 @@
 package org.bukkit.craftbukkit.entity;
 
-import java.util.List;
 import net.minecraft.world.entity.npc.EntityVillager;
 import net.minecraft.world.entity.npc.EntityVillagerAbstract;
+import net.minecraft.world.item.trading.IMerchant;
 import org.bukkit.craftbukkit.CraftServer;
 import org.bukkit.craftbukkit.inventory.CraftInventory;
 import org.bukkit.craftbukkit.inventory.CraftMerchant;
 import org.bukkit.entity.AbstractVillager;
-import org.bukkit.entity.HumanEntity;
 import org.bukkit.inventory.Inventory;
 import org.bukkit.inventory.InventoryHolder;
-import org.bukkit.inventory.MerchantRecipe;
 
-public class CraftAbstractVillager extends CraftAgeable implements AbstractVillager, InventoryHolder {
+public class CraftAbstractVillager extends CraftAgeable implements CraftMerchant, AbstractVillager, InventoryHolder {
 
     public CraftAbstractVillager(CraftServer server, EntityVillagerAbstract entity) {
         super(server, entity);
@@ -23,6 +21,11 @@ public class CraftAbstractVillager extends CraftAgeable implements AbstractVilla
         return (EntityVillager) entity;
     }
 
+    @Override
+    public IMerchant getMerchant() {
+        return getHandle();
+    }
+
     @Override
     public String toString() {
         return "CraftAbstractVillager";
@@ -32,43 +35,4 @@ public class CraftAbstractVillager extends CraftAgeable implements AbstractVilla
     public Inventory getInventory() {
         return new CraftInventory(getHandle().getInventory());
     }
-
-    private CraftMerchant getMerchant() {
-        return getHandle().getCraftMerchant();
-    }
-
-    @Override
-    public List<MerchantRecipe> getRecipes() {
-        return getMerchant().getRecipes();
-    }
-
-    @Override
-    public void setRecipes(List<MerchantRecipe> recipes) {
-        this.getMerchant().setRecipes(recipes);
-    }
-
-    @Override
-    public MerchantRecipe getRecipe(int i) {
-        return getMerchant().getRecipe(i);
-    }
-
-    @Override
-    public void setRecipe(int i, MerchantRecipe merchantRecipe) {
-        getMerchant().setRecipe(i, merchantRecipe);
-    }
-
-    @Override
-    public int getRecipeCount() {
-        return getMerchant().getRecipeCount();
-    }
-
-    @Override
-    public boolean isTrading() {
-        return getTrader() != null;
-    }
-
-    @Override
-    public HumanEntity getTrader() {
-        return getMerchant().getTrader();
-    }
 }

paper-server/src/main/java/org/bukkit/craftbukkit/inventory/CraftMerchant.java

@@ -11,21 +11,13 @@ import org.bukkit.entity.HumanEntity;
 import org.bukkit.inventory.Merchant;
 import org.bukkit.inventory.MerchantRecipe;
 
-public class CraftMerchant implements Merchant {
+public interface CraftMerchant extends Merchant {
 
-    protected final IMerchant merchant;
-
-    public CraftMerchant(IMerchant merchant) {
-        this.merchant = merchant;
-    }
-
-    public IMerchant getMerchant() {
-        return merchant;
-    }
+    IMerchant getMerchant();
 
     @Override
-    public List<MerchantRecipe> getRecipes() {
-        return Collections.unmodifiableList(Lists.transform(merchant.getOffers(), new Function<net.minecraft.world.item.trading.MerchantRecipe, MerchantRecipe>() {
+    default List<MerchantRecipe> getRecipes() {
+        return Collections.unmodifiableList(Lists.transform(getMerchant().getOffers(), new Function<net.minecraft.world.item.trading.MerchantRecipe, MerchantRecipe>() {
             @Override
             public MerchantRecipe apply(net.minecraft.world.item.trading.MerchantRecipe recipe) {
                 return recipe.asBukkit();
@@ -34,8 +26,8 @@ public class CraftMerchant implements Merchant {
     }
 
     @Override
-    public void setRecipes(List<MerchantRecipe> recipes) {
-        MerchantRecipeList recipesList = merchant.getOffers();
+    default void setRecipes(List<MerchantRecipe> recipes) {
+        MerchantRecipeList recipesList = getMerchant().getOffers();
         recipesList.clear();
         for (MerchantRecipe recipe : recipes) {
             recipesList.add(CraftMerchantRecipe.fromBukkit(recipe).toMinecraft());
@@ -43,38 +35,28 @@ public class CraftMerchant implements Merchant {
     }
 
     @Override
-    public MerchantRecipe getRecipe(int i) {
-        return merchant.getOffers().get(i).asBukkit();
+    default MerchantRecipe getRecipe(int i) {
+        return getMerchant().getOffers().get(i).asBukkit();
     }
 
     @Override
-    public void setRecipe(int i, MerchantRecipe merchantRecipe) {
-        merchant.getOffers().set(i, CraftMerchantRecipe.fromBukkit(merchantRecipe).toMinecraft());
+    default void setRecipe(int i, MerchantRecipe merchantRecipe) {
+        getMerchant().getOffers().set(i, CraftMerchantRecipe.fromBukkit(merchantRecipe).toMinecraft());
     }
 
     @Override
-    public int getRecipeCount() {
-        return merchant.getOffers().size();
+    default int getRecipeCount() {
+        return getMerchant().getOffers().size();
     }
 
     @Override
-    public boolean isTrading() {
+    default boolean isTrading() {
         return getTrader() != null;
     }
 
     @Override
-    public HumanEntity getTrader() {
-        EntityHuman eh = merchant.getTradingPlayer();
+    default HumanEntity getTrader() {
+        EntityHuman eh = getMerchant().getTradingPlayer();
         return eh == null ? null : eh.getBukkitEntity();
     }
-
-    @Override
-    public int hashCode() {
-        return merchant.hashCode();
-    }
-
-    @Override
-    public boolean equals(final Object obj) {
-        return obj instanceof CraftMerchant && ((CraftMerchant) obj).merchant.equals(this.merchant);
-    }
 }

paper-server/src/main/java/org/bukkit/craftbukkit/inventory/CraftMerchantCustom.java

@@ -11,10 +11,12 @@ import net.minecraft.world.item.trading.MerchantRecipe;
 import net.minecraft.world.item.trading.MerchantRecipeList;
 import org.bukkit.craftbukkit.util.CraftChatMessage;
 
-public class CraftMerchantCustom extends CraftMerchant {
+public class CraftMerchantCustom implements CraftMerchant {
+
+    private MinecraftMerchant merchant;
 
     public CraftMerchantCustom(String title) {
-        super(new MinecraftMerchant(title));
+        this.merchant = new MinecraftMerchant(title);
         getMerchant().craftMerchant = this;
     }
 
@@ -25,7 +27,7 @@ public class CraftMerchantCustom extends CraftMerchant {
 
     @Override
     public MinecraftMerchant getMerchant() {
-        return (MinecraftMerchant) super.getMerchant();
+        return this.merchant;
     }
 
     public static class MinecraftMerchant implements IMerchant {