From 2898b4a7eb7c477e57a6ce1ff47c1642d181186e Mon Sep 17 00:00:00 2001
From: chickeneer <emcchickeneer@gmail.com>
Date: Fri, 5 Jun 2020 20:02:04 -0500
Subject: [PATCH] Fix villager trading demand - MC-163962

Prevent demand from going negative and tending to negative infinity
---
 .../world/item/trading/MerchantOffer.java.patch          | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/paper-server/patches/sources/net/minecraft/world/item/trading/MerchantOffer.java.patch b/paper-server/patches/sources/net/minecraft/world/item/trading/MerchantOffer.java.patch
index a199c6a05a..b2a328fe58 100644
--- a/paper-server/patches/sources/net/minecraft/world/item/trading/MerchantOffer.java.patch
+++ b/paper-server/patches/sources/net/minecraft/world/item/trading/MerchantOffer.java.patch
@@ -29,6 +29,15 @@
      private MerchantOffer(ItemCost firstBuyItem, Optional<ItemCost> secondBuyItem, ItemStack sellItem, int uses, int maxUses, boolean rewardingPlayerExperience, int specialPrice, int demandBonus, float priceMultiplier, int merchantExperience) {
          this.baseCostA = firstBuyItem;
          this.costB = secondBuyItem;
+@@ -110,7 +124,7 @@
+     }
+ 
+     public void updateDemand() {
+-        this.demand = this.demand + this.uses - (this.maxUses - this.uses);
++        this.demand = Math.max(0, this.demand + this.uses - (this.maxUses - this.uses)); // Paper - Fix MC-163962
+     }
+ 
+     public ItemStack assemble() {
 @@ -185,7 +199,11 @@
          if (!this.satisfiedBy(firstBuyStack, secondBuyStack)) {
              return false;