Paper/patches/server/0975-Add-drops-to-shear-events.patch
Owen 89d51d5f29
Allow enabling sand duping (#10191)
Because this exploit has been widely known for years and has not been fixed by Mojang, we decided that it was worth allowing people to toggle it on/off due to how easy it is to make it configurable.

It should be noted that this decision does not promise all future exploits will be configurable.
2024-03-03 17:05:34 -05:00

327 lines
18 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Tue, 18 May 2021 12:32:02 -0700
Subject: [PATCH] Add drops to shear events
diff --git a/src/main/java/net/minecraft/core/dispenser/ShearsDispenseItemBehavior.java b/src/main/java/net/minecraft/core/dispenser/ShearsDispenseItemBehavior.java
index 45d356c1ed888b4d749379ceaa8a95d7d7c876d5..8d65cdb013706a932c2c73231108b2810b99e1c7 100644
--- a/src/main/java/net/minecraft/core/dispenser/ShearsDispenseItemBehavior.java
+++ b/src/main/java/net/minecraft/core/dispenser/ShearsDispenseItemBehavior.java
@@ -103,11 +103,14 @@ public class ShearsDispenseItemBehavior extends OptionalDispenseItemBehavior {
if (ishearable.readyForShearing()) {
// CraftBukkit start
- if (CraftEventFactory.callBlockShearEntityEvent(entityliving, bukkitBlock, craftItem).isCancelled()) {
+ // Paper start - Add drops to shear events
+ org.bukkit.event.block.BlockShearEntityEvent event = CraftEventFactory.callBlockShearEntityEvent(entityliving, bukkitBlock, craftItem, ishearable.generateDefaultDrops());
+ if (event.isCancelled()) {
+ // Paper end - Add drops to shear events
continue;
}
// CraftBukkit end
- ishearable.shear(SoundSource.BLOCKS);
+ ishearable.shear(SoundSource.BLOCKS, CraftItemStack.asNMSCopy(event.getDrops())); // Paper - Add drops to shear events
worldserver.gameEvent((Entity) null, GameEvent.SHEAR, blockposition);
return true;
}
diff --git a/src/main/java/net/minecraft/world/entity/Shearable.java b/src/main/java/net/minecraft/world/entity/Shearable.java
index 5e8cc5cfac8888628c6d513148f41be09ca65a2c..2ee48ac3b665db2b02bcb1a30ec972d43a3725b0 100644
--- a/src/main/java/net/minecraft/world/entity/Shearable.java
+++ b/src/main/java/net/minecraft/world/entity/Shearable.java
@@ -3,7 +3,13 @@ package net.minecraft.world.entity;
import net.minecraft.sounds.SoundSource;
public interface Shearable {
+ default void shear(SoundSource soundCategory, java.util.List<net.minecraft.world.item.ItemStack> drops) { this.shear(soundCategory); } // Paper - Add drops to shear events
void shear(SoundSource shearedSoundCategory);
boolean readyForShearing();
+ // Paper start - custom shear drops; ensure all implementing entities override this
+ default java.util.List<net.minecraft.world.item.ItemStack> generateDefaultDrops() {
+ return java.util.Collections.emptyList();
+ }
+ // Paper end - custom shear drops
}
diff --git a/src/main/java/net/minecraft/world/entity/animal/MushroomCow.java b/src/main/java/net/minecraft/world/entity/animal/MushroomCow.java
index 7243e4b95e98fda68d9e6adef0e41bebe825961a..161c128d27f50f145f88142191f1a5c93649ea65 100644
--- a/src/main/java/net/minecraft/world/entity/animal/MushroomCow.java
+++ b/src/main/java/net/minecraft/world/entity/animal/MushroomCow.java
@@ -123,11 +123,18 @@ public class MushroomCow extends Cow implements Shearable, VariantHolder<Mushroo
return InteractionResult.sidedSuccess(this.level().isClientSide);
} else if (itemstack.is(Items.SHEARS) && this.readyForShearing()) {
// CraftBukkit start
- if (!CraftEventFactory.handlePlayerShearEntityEvent(player, this, itemstack, hand)) {
- return InteractionResult.PASS;
+ // Paper start - custom shear drops
+ List<ItemStack> drops = this.generateDefaultDrops();
+ org.bukkit.event.player.PlayerShearEntityEvent event = CraftEventFactory.handlePlayerShearEntityEvent(player, this, itemstack, hand, drops);
+ if (event != null) {
+ if (event.isCancelled()) {
+ return InteractionResult.PASS;
+ }
+ drops = org.bukkit.craftbukkit.inventory.CraftItemStack.asNMSCopy(event.getDrops());
}
+ // Paper end - custom shear drops
// CraftBukkit end
- this.shear(SoundSource.PLAYERS);
+ this.shear(SoundSource.PLAYERS, drops); // Paper - custom shear drops
this.gameEvent(GameEvent.SHEAR, player);
if (!this.level().isClientSide) {
itemstack.hurtAndBreak(1, player, (entityhuman1) -> {
@@ -168,6 +175,22 @@ public class MushroomCow extends Cow implements Shearable, VariantHolder<Mushroo
@Override
public void shear(SoundSource shearedSoundCategory) {
+ // Paper start - custom shear drops
+ this.shear(shearedSoundCategory, this.generateDefaultDrops());
+ }
+
+ @Override
+ public List<ItemStack> generateDefaultDrops() {
+ List<ItemStack> dropEntities = new java.util.ArrayList<>(5);
+ for (int i = 0; i < 5; ++i) {
+ dropEntities.add(new ItemStack(this.getVariant().getBlockState().getBlock()));
+ }
+ return dropEntities;
+ }
+
+ @Override
+ public void shear(SoundSource shearedSoundCategory, List<ItemStack> drops) { // If drops is null, need to generate drops
+ // Paper end - custom shear drops
this.level().playSound((Player) null, (Entity) this, SoundEvents.MOOSHROOM_SHEAR, shearedSoundCategory, 1.0F, 1.0F);
if (!this.level().isClientSide()) {
Cow entitycow = (Cow) EntityType.COW.create(this.level());
@@ -197,17 +220,12 @@ public class MushroomCow extends Cow implements Shearable, VariantHolder<Mushroo
this.discard(EntityRemoveEvent.Cause.TRANSFORMATION); // CraftBukkit - from above and add Bukkit remove cause
// CraftBukkit end
- for (int i = 0; i < 5; ++i) {
- // CraftBukkit start
- ItemEntity entityitem = new ItemEntity(this.level(), this.getX(), this.getY(1.0D), this.getZ(), new ItemStack(this.getVariant().blockState.getBlock()));
- EntityDropItemEvent event = new EntityDropItemEvent(this.getBukkitEntity(), (org.bukkit.entity.Item) entityitem.getBukkitEntity());
- Bukkit.getPluginManager().callEvent(event);
- if (event.isCancelled()) {
- continue;
- }
- this.level().addFreshEntity(entityitem);
- // CraftBukkit end
+ // Paper start - custom shear drops; moved drop generation to separate method
+ for (final ItemStack drop : drops) {
+ ItemEntity entityitem = new ItemEntity(this.level(), this.getX(), this.getY(1.0D), this.getZ(), drop);
+ this.spawnAtLocation(entityitem);
}
+ // Paper end - custom shear drops
}
}
diff --git a/src/main/java/net/minecraft/world/entity/animal/Sheep.java b/src/main/java/net/minecraft/world/entity/animal/Sheep.java
index 55afa58f3df53ce548c7484d8fff62c903f9dc07..1d80678f7e8f658e43616f0baf723f096a99122a 100644
--- a/src/main/java/net/minecraft/world/entity/animal/Sheep.java
+++ b/src/main/java/net/minecraft/world/entity/animal/Sheep.java
@@ -253,11 +253,18 @@ public class Sheep extends Animal implements Shearable {
if (itemstack.is(Items.SHEARS)) {
if (!this.level().isClientSide && this.readyForShearing()) {
// CraftBukkit start
- if (!CraftEventFactory.handlePlayerShearEntityEvent(player, this, itemstack, hand)) {
- return InteractionResult.PASS;
+ // Paper start - custom shear drops
+ java.util.List<ItemStack> drops = this.generateDefaultDrops();
+ org.bukkit.event.player.PlayerShearEntityEvent event = CraftEventFactory.handlePlayerShearEntityEvent(player, this, itemstack, hand, drops);
+ if (event != null) {
+ if (event.isCancelled()) {
+ return InteractionResult.PASS;
+ }
+ drops = org.bukkit.craftbukkit.inventory.CraftItemStack.asNMSCopy(event.getDrops());
}
+ // Paper end - custom shear drops
// CraftBukkit end
- this.shear(SoundSource.PLAYERS);
+ this.shear(SoundSource.PLAYERS, drops); // Paper
this.gameEvent(GameEvent.SHEAR, player);
itemstack.hurtAndBreak(1, player, (entityhuman1) -> {
entityhuman1.broadcastBreakEvent(hand);
@@ -273,13 +280,30 @@ public class Sheep extends Animal implements Shearable {
@Override
public void shear(SoundSource shearedSoundCategory) {
+ // Paper start - custom shear drops
+ this.shear(shearedSoundCategory, this.generateDefaultDrops());
+ }
+
+ @Override
+ public java.util.List<ItemStack> generateDefaultDrops() {
+ int count = 1 + this.random.nextInt(3);
+ java.util.List<ItemStack> dropEntities = new java.util.ArrayList<>(count);
+ for (int j = 0; j < count; ++j) {
+ dropEntities.add(new ItemStack(Sheep.ITEM_BY_DYE.get(this.getColor())));
+ }
+ return dropEntities;
+ }
+
+ @Override
+ public void shear(SoundSource shearedSoundCategory, java.util.List<ItemStack> drops) {
+ // Paper end - custom shear drops
this.level().playSound((Player) null, (Entity) this, SoundEvents.SHEEP_SHEAR, shearedSoundCategory, 1.0F, 1.0F);
this.setSheared(true);
int i = 1 + this.random.nextInt(3);
- for (int j = 0; j < i; ++j) {
+ for (final ItemStack drop : drops) { // Paper - custom shear drops (moved drop generation to separate method)
this.forceDrops = true; // CraftBukkit
- ItemEntity entityitem = this.spawnAtLocation((ItemLike) Sheep.ITEM_BY_DYE.get(this.getColor()), 1);
+ ItemEntity entityitem = this.spawnAtLocation(drop, 1); // Paper - custom shear drops
this.forceDrops = false; // CraftBukkit
if (entityitem != null) {
diff --git a/src/main/java/net/minecraft/world/entity/animal/SnowGolem.java b/src/main/java/net/minecraft/world/entity/animal/SnowGolem.java
index 54c01fdaf507a30196fb8f38888a570f9e393559..9eab1170cb123d3b60a02314702516704f959ab7 100644
--- a/src/main/java/net/minecraft/world/entity/animal/SnowGolem.java
+++ b/src/main/java/net/minecraft/world/entity/animal/SnowGolem.java
@@ -153,11 +153,18 @@ public class SnowGolem extends AbstractGolem implements Shearable, RangedAttackM
if (itemstack.is(Items.SHEARS) && this.readyForShearing()) {
// CraftBukkit start
- if (!CraftEventFactory.handlePlayerShearEntityEvent(player, this, itemstack, hand)) {
- return InteractionResult.PASS;
+ // Paper start - custom shear drops
+ java.util.List<ItemStack> drops = this.generateDefaultDrops();
+ org.bukkit.event.player.PlayerShearEntityEvent event = CraftEventFactory.handlePlayerShearEntityEvent(player, this, itemstack, hand, drops);
+ if (event != null) {
+ if (event.isCancelled()) {
+ return InteractionResult.PASS;
+ }
+ drops = org.bukkit.craftbukkit.inventory.CraftItemStack.asNMSCopy(event.getDrops());
}
+ // Paper end - custom shear drops
// CraftBukkit end
- this.shear(SoundSource.PLAYERS);
+ this.shear(SoundSource.PLAYERS, drops); // Paper
this.gameEvent(GameEvent.SHEAR, player);
if (!this.level().isClientSide) {
itemstack.hurtAndBreak(1, player, (entityhuman1) -> {
@@ -173,12 +180,28 @@ public class SnowGolem extends AbstractGolem implements Shearable, RangedAttackM
@Override
public void shear(SoundSource shearedSoundCategory) {
+ // Paper start - custom shear drops
+ this.shear(shearedSoundCategory, this.generateDefaultDrops());
+ }
+
+ @Override
+ public java.util.List<ItemStack> generateDefaultDrops() {
+ return java.util.Collections.singletonList(new ItemStack(Items.CARVED_PUMPKIN));
+ }
+
+ @Override
+ public void shear(SoundSource shearedSoundCategory, java.util.List<ItemStack> drops) {
+ // Paper end - custom shear drops
this.level().playSound((Player) null, (Entity) this, SoundEvents.SNOW_GOLEM_SHEAR, shearedSoundCategory, 1.0F, 1.0F);
if (!this.level().isClientSide()) {
this.setPumpkin(false);
- this.forceDrops = true; // CraftBukkit
- this.spawnAtLocation(new ItemStack(Items.CARVED_PUMPKIN), 1.7F);
- this.forceDrops = false; // CraftBukkit
+ // Paper start - custom shear drops (moved drop generation to separate method)
+ for (final ItemStack drop : drops) {
+ this.forceDrops = true;
+ this.spawnAtLocation(drop, 1.7F);
+ this.forceDrops = false;
+ }
+ // Paper end - custom shear drops
}
}
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index f2f58ae16101293a7df53c32be015111baba1504..4c2e8129481384a143384d327e14320023735b1a 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -1668,20 +1668,20 @@ public class CraftEventFactory {
return event;
}
- public static BlockShearEntityEvent callBlockShearEntityEvent(Entity animal, org.bukkit.block.Block dispenser, CraftItemStack is) {
- BlockShearEntityEvent bse = new BlockShearEntityEvent(dispenser, animal.getBukkitEntity(), is);
+ public static BlockShearEntityEvent callBlockShearEntityEvent(Entity animal, Block dispenser, CraftItemStack is, List<ItemStack> drops) { // Paper - custom shear drops
+ BlockShearEntityEvent bse = new BlockShearEntityEvent(dispenser, animal.getBukkitEntity(), is, Lists.transform(drops, CraftItemStack::asCraftMirror)); // Paper - custom shear drops
Bukkit.getPluginManager().callEvent(bse);
return bse;
}
- public static boolean handlePlayerShearEntityEvent(net.minecraft.world.entity.player.Player player, Entity sheared, ItemStack shears, InteractionHand hand) {
+ public static PlayerShearEntityEvent handlePlayerShearEntityEvent(net.minecraft.world.entity.player.Player player, Entity sheared, ItemStack shears, InteractionHand hand, List<ItemStack> drops) { // Paper - custom shear drops
if (!(player instanceof ServerPlayer)) {
- return true;
+ return null; // Paper - custom shear drops
}
- PlayerShearEntityEvent event = new PlayerShearEntityEvent((Player) player.getBukkitEntity(), sheared.getBukkitEntity(), CraftItemStack.asCraftMirror(shears), (hand == InteractionHand.OFF_HAND ? EquipmentSlot.OFF_HAND : EquipmentSlot.HAND));
+ PlayerShearEntityEvent event = new PlayerShearEntityEvent((Player) player.getBukkitEntity(), sheared.getBukkitEntity(), CraftItemStack.asCraftMirror(shears), (hand == InteractionHand.OFF_HAND ? EquipmentSlot.OFF_HAND : EquipmentSlot.HAND), Lists.transform(drops, CraftItemStack::asCraftMirror)); // Paper - custom shear drops
Bukkit.getPluginManager().callEvent(event);
- return !event.isCancelled();
+ return event; // Paper - custom shear drops
}
public static Cancellable handleStatisticsIncrease(net.minecraft.world.entity.player.Player entityHuman, net.minecraft.stats.Stat<?> statistic, int current, int newValue) {
diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
index e1f9a603e7adf3468faa9bb6d93dd3339327b47e..870954fc59efdc1e0c6b5047f5a89dfaf7522d0e 100644
--- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
+++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
@@ -62,6 +62,16 @@ public final class CraftItemStack extends ItemStack {
return stack;
}
+ // Paper start
+ public static java.util.List<net.minecraft.world.item.ItemStack> asNMSCopy(java.util.List<? extends ItemStack> originals) {
+ final java.util.List<net.minecraft.world.item.ItemStack> items = new java.util.ArrayList<>(originals.size());
+ for (final ItemStack original : originals) {
+ items.add(asNMSCopy(original));
+ }
+ return items;
+ }
+ // Paper end
+
public static net.minecraft.world.item.ItemStack copyNMSStack(net.minecraft.world.item.ItemStack original, int amount) {
net.minecraft.world.item.ItemStack stack = original.copy();
stack.setCount(amount);
diff --git a/src/test/java/io/papermc/paper/entity/ShearableDropsTest.java b/src/test/java/io/papermc/paper/entity/ShearableDropsTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..e612515f7709dbe5d1fa5751337cdc34fce10a98
--- /dev/null
+++ b/src/test/java/io/papermc/paper/entity/ShearableDropsTest.java
@@ -0,0 +1,34 @@
+package io.papermc.paper.entity;
+
+import io.github.classgraph.ClassGraph;
+import io.github.classgraph.ClassInfo;
+import io.github.classgraph.MethodInfoList;
+import io.github.classgraph.ScanResult;
+import java.util.ArrayList;
+import net.minecraft.world.entity.Shearable;
+import org.bukkit.support.AbstractTestingBase;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class ShearableDropsTest extends AbstractTestingBase {
+
+ static Iterable<ClassInfo> parameters() {
+ try (ScanResult scanResult = new ClassGraph()
+ .enableClassInfo()
+ .enableMethodInfo()
+ .whitelistPackages("net.minecraft")
+ .scan()
+ ) {
+ return new ArrayList<>(scanResult.getClassesImplementing(Shearable.class.getName()));
+ }
+ }
+
+ @ParameterizedTest
+ @MethodSource("parameters")
+ void checkShearableDropOverrides(final ClassInfo classInfo) {
+ final MethodInfoList generateDefaultDrops = classInfo.getDeclaredMethodInfo("generateDefaultDrops");
+ assertEquals(1, generateDefaultDrops.size(), classInfo.getName() + " doesn't implement Shearable#generateDefaultDrops");
+ }
+}