PaperMC/patches/server/0978-Fix-cancelling-BlockPlaceEvent-calling-onRemove.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Tamion <70228790+notTamion@users.noreply.github.com>
Date: Thu, 23 May 2024 11:02:20 +0200
Subject: [PATCH] Fix cancelling BlockPlaceEvent calling onRemove


diff --git a/src/main/java/net/minecraft/world/item/ItemStack.java b/src/main/java/net/minecraft/world/item/ItemStack.java
index 8309d2f7872ccdbc9d76f0fbf481411f74080148..de32bf4947af8d2ec64e8799580a129b038dd35e 100644
--- a/src/main/java/net/minecraft/world/item/ItemStack.java
+++ b/src/main/java/net/minecraft/world/item/ItemStack.java
@@ -494,9 +494,11 @@ public final class ItemStack implements DataComponentHolder {
                     world.capturedTileEntities.clear(); // Paper - Allow chests to be placed with NBT data; clear out block entities as chests and such will pop loot
                     // revert back all captured blocks
                     world.preventPoiUpdated = true; // CraftBukkit - SPIGOT-5710
+                    world.isBlockPlaceCancelled = true; // Paper - prevent calling cleanup logic when undoing a block place upon a cancelled BlockPlaceEvent
                     for (BlockState blockstate : blocks) {
                         blockstate.update(true, false);
                     }
+                    world.isBlockPlaceCancelled = false; // Paper - prevent calling cleanup logic when undoing a block place upon a cancelled BlockPlaceEvent
                     world.preventPoiUpdated = false;
 
                     // Brute force all possible updates
diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
index c6c9400fa155831ab11d0f059971d0123617e622..e27d3547d1e19c137e05e6b8d075127a8bafb237 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -151,6 +151,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
     public boolean preventPoiUpdated = false; // CraftBukkit - SPIGOT-5710
     public boolean captureBlockStates = false;
     public boolean captureTreeGeneration = false;
+    public boolean isBlockPlaceCancelled = false; // Paper - prevent calling cleanup logic when undoing a block place upon a cancelled BlockPlaceEvent
     public Map<BlockPos, org.bukkit.craftbukkit.block.CraftBlockState> capturedBlockStates = new java.util.LinkedHashMap<>(); // Paper
     public Map<BlockPos, BlockEntity> capturedTileEntities = new java.util.LinkedHashMap<>(); // Paper - Retain block place order when capturing blockstates
     public List<ItemEntity> captureDrops;
diff --git a/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java b/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java
index 7f8983a2102787b13e5d28d6981055da6acd1012..602ad80c2b93d320bf2a25832d25a58cb8c72e4b 100644
--- a/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java
+++ b/src/main/java/net/minecraft/world/level/chunk/LevelChunk.java
@@ -345,7 +345,7 @@ public class LevelChunk extends ChunkAccess {
 
                 boolean flag3 = iblockdata1.hasBlockEntity();
 
-                if (!this.level.isClientSide) {
+                if (!this.level.isClientSide && !this.level.isBlockPlaceCancelled) { // Paper - prevent calling cleanup logic when undoing a block place upon a cancelled BlockPlaceEvent
                     iblockdata1.onRemove(this.level, blockposition, iblockdata, flag);
                 } else if (!iblockdata1.is(block) && flag3) {
                     this.removeBlockEntity(blockposition);