From 90be3474fa66dfd953259517ebc0a80f2262b58f 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 e4502551..9f5388ed 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -1153,7 +1153,7 @@ public abstract class World implements IBlockAccess {
                 for (Entity e : entities) {
                     if (e instanceof EntityExperienceOrb) {
                         EntityExperienceOrb loopItem = (EntityExperienceOrb) e;
-                        if (!loopItem.dead && !(maxValue > 0 && loopItem.value >= maxValue)) { // Paper
+                        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()) { // Paper
                             xp.value += loopItem.value;
                             // Paper start
                             if (!mergeUnconditionally && xp.value > maxValue) {
-- 
2.14.3