From a52f0dc0ac68a35e4ba71589eeab5fe3e1e06e84 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 d40725b17a..0f56969270 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -1015,7 +1015,7 @@ public abstract class World implements GeneratorAccess, IIBlockAccess, AutoClose
                     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 (newTotal > (long)maxValue) {
                                 loopItem.value = xp.value - maxValue;
-- 
2.18.0