From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sun, 27 Dec 2020 11:31:06 +0000
Subject: [PATCH] Do not crash from invalid ingredient lists in
 VillagerAcquireTradeEvent


diff --git a/src/main/java/net/minecraft/server/EntityVillagerAbstract.java b/src/main/java/net/minecraft/server/EntityVillagerAbstract.java
index 790df2be9cbbc359ba354ed272dbf6dda71951f0..4620c36d568da12092a2f7cb067cbf7fd20bee94 100644
--- a/src/main/java/net/minecraft/server/EntityVillagerAbstract.java
+++ b/src/main/java/net/minecraft/server/EntityVillagerAbstract.java
@@ -246,7 +246,11 @@ public abstract class EntityVillagerAbstract extends EntityAgeable implements NP
                     Bukkit.getPluginManager().callEvent(event);
                 }
                 if (!event.isCancelled()) {
-                    merchantrecipelist.add(CraftMerchantRecipe.fromBukkit(event.getRecipe()).toMinecraft());
+                    // Paper start
+                    final CraftMerchantRecipe craftMerchantRecipe = CraftMerchantRecipe.fromBukkit(event.getRecipe());
+                    if (craftMerchantRecipe.getIngredients().isEmpty()) return;
+                    merchantrecipelist.add(craftMerchantRecipe.toMinecraft());
+                    // Paper end
                 }
                 // CraftBukkit end
             }