Folia/patches/server/0014-Do-not-access-POI-data-for-lodestone-compass.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sat, 13 May 2023 17:13:40 -0700
Subject: [PATCH] Do not access POI data for lodestone compass

Instead, we can just check the loaded chunk's block position for
the lodestone block, as that is at least safe enough for the light
engine compared to the POI access. This should make it safe for
off-region access.

diff --git a/src/main/java/net/minecraft/world/item/CompassItem.java b/src/main/java/net/minecraft/world/item/CompassItem.java
index b3c67c954acf7e518d89d6af65a55d6f22dac059..eea1066379805a4bdef9b496a92ad956d0c84ac7 100644
--- a/src/main/java/net/minecraft/world/item/CompassItem.java
+++ b/src/main/java/net/minecraft/world/item/CompassItem.java
@@ -77,7 +77,10 @@ public class CompassItem extends Item implements Vanishable {
                 Optional<ResourceKey<Level>> optional = getLodestoneDimension(compoundTag);
                 if (optional.isPresent() && optional.get() == world.dimension() && compoundTag.contains("LodestonePos")) {
                     BlockPos blockPos = NbtUtils.readBlockPos(compoundTag.getCompound("LodestonePos"));
-                    if (!world.isInWorldBounds(blockPos) || (world.hasChunkAt(blockPos) && !((ServerLevel)world).getPoiManager().existsAtPosition(PoiTypes.LODESTONE, blockPos))) { // Paper - Prevent compass from loading chunks
+                    // Folia start - do not access the POI data off-region
+                    net.minecraft.world.level.chunk.LevelChunk chunk = world.getChunkIfLoaded(blockPos);
+                    if (!world.isInWorldBounds(blockPos) || chunk != null && chunk.getBlockState(blockPos).getBlock() != Blocks.LODESTONE) { // Paper - Prevent compass from loading chunks
+                        // Folia end - do not access the POI data off-region
                         compoundTag.remove("LodestonePos");
                     }
                 }