From e7daf06af73e4ae7aec0982e034bd1ef4d35718f Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 19 Dec 2017 22:57:26 -0500
Subject: [PATCH] ExperienceOrbMergeEvent

Fired when the server is about to merge 2 experience orbs
Plugins can cancel this if they want to ensure experience orbs do not lose important
metadata such as spawn reason, or conditionally move data from source to target.

diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 2ddc3f050..a14518ba6 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -1042,7 +1042,7 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
                     if (e instanceof EntityExperienceOrb) {
                         EntityExperienceOrb loopItem = (EntityExperienceOrb) e;
                         // Paper start
-                        if (!loopItem.dead && !(maxValue > 0 && loopItem.value >= maxValue)) {
+                        if (!loopItem.dead && !(maxValue > 0 && loopItem.value >= maxValue) && new com.destroystokyo.paper.event.entity.ExperienceOrbMergeEvent((org.bukkit.entity.ExperienceOrb) entity.getBukkitEntity(), (org.bukkit.entity.ExperienceOrb) loopItem.getBukkitEntity()).callEvent()) {
                             long newTotal = (long)xp.value + (long)loopItem.value;
                             if ((int) newTotal < 0) continue; // Overflow
                             if (maxValue > 0 && newTotal > (long)maxValue) {
-- 
2.20.0