Add EnderManAngerEvent to make it possible to prevent endermen getting angry at a player based on more then their helmet. (#8406)

patches/minecraft/net/minecraft/world/entity/monster/EnderMan.java.patch

@@ -21,7 +21,7 @@
     boolean m_32534_(Player p_32535_) {
        ItemStack itemstack = p_32535_.m_150109_().f_35975_.get(3);
 -      if (itemstack.m_150930_(Blocks.f_50143_.m_5456_())) {
-+      if (itemstack.isEnderMask(p_32535_, this)) {
++      if (net.minecraftforge.common.ForgeHooks.shouldSuppressEnderManAnger(this, p_32535_, itemstack)) {
           return false;
        } else {
           Vec3 vec3 = p_32535_.m_20252_(1.0F).m_82541_();

src/main/java/net/minecraftforge/common/ForgeHooks.java

@@ -16,7 +16,6 @@ import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Objects;
-import java.util.Optional;
 import java.util.Set;
 import java.util.Map.Entry;
 import java.util.Optional;
@@ -57,6 +56,7 @@ import net.minecraft.world.entity.ai.attributes.AttributeModifier;
 import net.minecraft.world.entity.ai.attributes.AttributeSupplier;
 import net.minecraft.world.entity.ai.attributes.DefaultAttributes;
 import net.minecraft.world.entity.EquipmentSlot;
+import net.minecraft.world.entity.monster.EnderMan;
 import net.minecraft.world.item.*;
 import net.minecraft.world.item.crafting.Ingredient;
 import net.minecraft.world.item.crafting.RecipeType;
@@ -133,6 +133,7 @@ import net.minecraftforge.event.entity.EntityAttributeModificationEvent;
 import net.minecraftforge.event.entity.EntityEvent;
 import net.minecraftforge.event.entity.EntityTravelToDimensionEvent;
 import net.minecraftforge.event.entity.item.ItemTossEvent;
+import net.minecraftforge.event.entity.living.EnderManAngerEvent;
 import net.minecraftforge.event.entity.living.LivingAttackEvent;
 import net.minecraftforge.event.entity.living.LivingDamageEvent;
 import net.minecraftforge.event.entity.living.LivingDeathEvent;
@@ -1479,4 +1480,9 @@ public class ForgeHooks
         }
     }
 
+    public static boolean shouldSuppressEnderManAnger(EnderMan enderMan, Player player, ItemStack mask)
+    {
+        return mask.isEnderMask(player, enderMan) || MinecraftForge.EVENT_BUS.post(new EnderManAngerEvent(enderMan, player));
+    }
+
 }

src/main/java/net/minecraftforge/event/entity/living/EnderManAngerEvent.java

@@ -0,0 +1,45 @@
+/*
+ * Minecraft Forge - Forge Development LLC
+ * SPDX-License-Identifier: LGPL-2.1-only
+ */
+
+package net.minecraftforge.event.entity.living;
+
+import net.minecraft.world.entity.monster.EnderMan;
+import net.minecraft.world.entity.player.Player;
+import net.minecraftforge.eventbus.api.Cancelable;
+
+/**
+ * This event is fired on the forge bus before an Enderman detects that a player is looking at them.
+ * It will not be fired if the detection is already prevented by {@link IForgeItem#isEnderMask}
+ * <p>
+ * This event is {@link Cancelable}.
+ * If this event is canceled, the Enderman will not target the player.
+ * <p>
+ * This event does not have a {@link Result}.
+ */
+@Cancelable
+public class EnderManAngerEvent extends LivingEvent
+{
+    private final Player player;
+
+    public EnderManAngerEvent(EnderMan enderman, Player player)
+    {
+        super(enderman);
+        this.player = player;
+    }
+
+    /**
+     * The player that is being checked.
+     */
+    public Player getPlayer()
+    {
+        return player;
+    }
+
+    @Override
+    public EnderMan getEntity()
+    {
+        return (EnderMan) super.getEntity();
+    }
+}