PaperMC/patches/server/0932-Lazily-create-LootContext-for-criterions.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: MrPowerGamerBR <git@mrpowergamerbr.com>
Date: Tue, 21 Nov 2023 12:16:39 -0300
Subject: [PATCH] Lazily create LootContext for criterions

For each player on each tick, enter block triggers are invoked, and these create loot contexts that are promptly thrown away since the trigger doesn't pass the predicate

To avoid this, we now lazily create the LootContext if the criterion passes the predicate AND if any of the listener triggers require a loot context instance

diff --git a/src/main/java/net/minecraft/advancements/critereon/SimpleCriterionTrigger.java b/src/main/java/net/minecraft/advancements/critereon/SimpleCriterionTrigger.java
index f43053ba082f9772b6ec02828fa2d6f387c32d26..35772110e9318df46a2729dbc0b5879b290011b7 100644
--- a/src/main/java/net/minecraft/advancements/critereon/SimpleCriterionTrigger.java
+++ b/src/main/java/net/minecraft/advancements/critereon/SimpleCriterionTrigger.java
@@ -42,14 +42,14 @@ public abstract class SimpleCriterionTrigger<T extends SimpleCriterionTrigger.Si
         PlayerAdvancements playerAdvancements = player.getAdvancements();
         Set<CriterionTrigger.Listener<T>> set = (Set) playerAdvancements.criterionData.get(this); // Paper - fix AdvancementDataPlayer leak
         if (set != null && !set.isEmpty()) {
-            LootContext lootContext = EntityPredicate.createContext(player, player);
+            LootContext lootContext = null; // EntityPredicate.createContext(player, player); // Paper - Perf: lazily create LootContext for criterions
             List<CriterionTrigger.Listener<T>> list = null;
 
             for (CriterionTrigger.Listener<T> listener : set) {
                 T simpleInstance = listener.trigger();
                 if (predicate.test(simpleInstance)) {
                     Optional<ContextAwarePredicate> optional = simpleInstance.player();
-                    if (optional.isEmpty() || optional.get().matches(lootContext)) {
+                    if (optional.isEmpty() || optional.get().matches(lootContext = (lootContext == null ? EntityPredicate.createContext(player, player) : lootContext))) { // Paper - Perf: lazily create LootContext for criterions
                         if (list == null) {
                             list = Lists.newArrayList();
                         }