From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 28 Mar 2016 19:55:45 -0400
Subject: [PATCH] Only process BlockPhysicsEvent if a plugin has a listener

Saves on some object allocation and processing when no plugin listens to this

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 4f1204661e345462c08cc66e3a8851033f186268..a37f11633663e07652274707b29a849e518511c5 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1544,6 +1544,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
 
         while (iterator.hasNext()) {
             ServerLevel worldserver = (ServerLevel) iterator.next();
+            worldserver.hasPhysicsEvent = org.bukkit.event.block.BlockPhysicsEvent.getHandlerList().getRegisteredListeners().length > 0; // Paper - BlockPhysicsEvent
 
             this.profiler.push(() -> {
                 String s = String.valueOf(worldserver);
diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index de1708e5d39561115d2825eea4a5f6e1f1f4e5b8..1e5b42fc3903b14537d232c8adbbaf79078d8d8e 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -227,6 +227,7 @@ public class ServerLevel extends Level implements WorldGenLevel {
     // CraftBukkit start
     public final LevelStorageSource.LevelStorageAccess convertable;
     public final UUID uuid;
+    public boolean hasPhysicsEvent = true; // Paper - BlockPhysicsEvent
 
     public LevelChunk getChunkIfLoaded(int x, int z) {
         return this.chunkSource.getChunk(x, z, false);
diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
index eae1d6eedeed09b3f49913c2bb205b80442bbfe3..622ecc1aeb9140d5c0d181fa472d123c42e5c5f4 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -491,7 +491,7 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
                 // CraftBukkit start
                 iblockdata1.updateIndirectNeighbourShapes(this, blockposition, k, j - 1); // Don't call an event for the old block to limit event spam
                 CraftWorld world = ((ServerLevel) this).getWorld();
-                if (world != null) {
+                if (world != null && ((ServerLevel)this).hasPhysicsEvent) { // Paper - BlockPhysicsEvent
                     BlockPhysicsEvent event = new BlockPhysicsEvent(world.getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ()), CraftBlockData.fromData(iblockdata));
                     this.getCraftServer().getPluginManager().callEvent(event);
 
diff --git a/src/main/java/net/minecraft/world/level/block/BushBlock.java b/src/main/java/net/minecraft/world/level/block/BushBlock.java
index 75109c79daa724340268438725bbf6d39b955691..a7b4b5600e3c889c69ac22294899713d50b5fe5c 100644
--- a/src/main/java/net/minecraft/world/level/block/BushBlock.java
+++ b/src/main/java/net/minecraft/world/level/block/BushBlock.java
@@ -28,7 +28,7 @@ public abstract class BushBlock extends Block {
     protected BlockState updateShape(BlockState state, Direction direction, BlockState neighborState, LevelAccessor world, BlockPos pos, BlockPos neighborPos) {
         // CraftBukkit start
         if (!state.canSurvive(world, pos)) {
-            if (!org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) {
+            if (!(world instanceof net.minecraft.server.level.ServerLevel && ((net.minecraft.server.level.ServerLevel) world).hasPhysicsEvent) || !org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) { // Paper
                 return Blocks.AIR.defaultBlockState();
             }
         }
diff --git a/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java b/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java
index cb76568cd1f97024c7a40328d9d72dd8a3e72e8b..7fdf744a2be55313cc75c1322f6534f55cf463f5 100644
--- a/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java
+++ b/src/main/java/net/minecraft/world/level/block/DoublePlantBlock.java
@@ -102,7 +102,7 @@ public class DoublePlantBlock extends BushBlock {
 
     protected static void preventDropFromBottomPart(Level world, BlockPos pos, BlockState state, Player player) {
         // CraftBukkit start
-        if (org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) {
+        if (((net.minecraft.server.level.ServerLevel)world).hasPhysicsEvent && org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPhysicsEvent(world, pos).isCancelled()) { // Paper
             return;
         }
         // CraftBukkit end