Add ShieldBlockEvent (#8261)

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

@@ -153,6 +153,7 @@ import net.minecraftforge.event.entity.living.LivingHurtEvent;
 import net.minecraftforge.event.entity.living.LivingKnockBackEvent;
 import net.minecraftforge.event.entity.living.LivingSetAttackTargetEvent;
 import net.minecraftforge.event.entity.living.LootingLevelEvent;
+import net.minecraftforge.event.entity.living.ShieldBlockEvent;
 import net.minecraftforge.event.entity.player.AdvancementEvent;
 import net.minecraftforge.event.entity.player.AnvilRepairEvent;
 import net.minecraftforge.event.entity.player.AttackEntityEvent;
@@ -1257,7 +1258,14 @@ public class ForgeHooks
     {
         MinecraftForge.EVENT_BUS.post(new EntityEvent.EnteringSection(entity, packedOldPos, packedNewPos));
     }
-    
+
+    public static ShieldBlockEvent onShieldBlock(LivingEntity blocker, DamageSource source, float blocked)
+    {
+        ShieldBlockEvent e = new ShieldBlockEvent(blocker, source, blocked);
+        MinecraftForge.EVENT_BUS.post(e);
+        return e;
+    }
+
     /**
      * Called when dimension jsons are parsed.
      * Creates a copy of the worldgen settings and its dimension registry,

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

@@ -0,0 +1,101 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2016-2021.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.event.entity.living;
+
+import net.minecraft.util.Mth;
+import net.minecraft.world.damagesource.DamageSource;
+import net.minecraft.world.entity.LivingEntity;
+import net.minecraftforge.eventbus.api.Cancelable;
+
+/**
+ * The ShieldBlockEvent is fired when an entity successfully blocks with a shield.<br>
+ * Cancelling this event will have the same impact as if the shield was not eligible to block.<br>
+ * The damage blocked cannot be set lower than zero or greater than the original value.<br>
+ * Note: The shield item stack "should" be available from {@link LivingEntity#getUseItem()}
+ * at least for players.
+ */
+@Cancelable
+public class ShieldBlockEvent extends LivingEvent
+{
+    private final DamageSource source;
+    private final float originalBlocked;
+    private float dmgBlocked;
+    private boolean shieldTakesDamage = true;
+
+    public ShieldBlockEvent(LivingEntity blocker, DamageSource source, float blocked)
+    {
+        super(blocker);
+        this.source = source;
+        this.originalBlocked = blocked;
+        this.dmgBlocked = blocked;
+    }
+
+    /**
+     * @return The damage source.
+     */
+    public DamageSource getDamageSource()
+    {
+        return this.source;
+    }
+
+    /**
+     * @return The original amount of damage blocked, which is the same as the original
+     * incoming damage value.
+     */
+    public float getOriginalBlockedDamage()
+    {
+        return this.originalBlocked;
+    }
+
+    /**
+     * @return The current amount of damage blocked, as a result of this event.
+     */
+    public float getBlockedDamage()
+    {
+        return this.dmgBlocked;
+    }
+
+    /**
+     * Controls if {@link LivingEntity#hurtCurrentlyUsedShield} is called.
+     * @return If the shield item will take durability damage or not.
+     */
+    public boolean shieldTakesDamage()
+    {
+        return this.shieldTakesDamage;
+    }
+
+    /**
+     * Set how much damage is blocked by this action.<br>
+     * Note that initially the blocked amount is the entire attack.<br>
+     */
+    public void setBlockedDamage(float blocked)
+    {
+        this.dmgBlocked = Mth.clamp(blocked, 0, this.originalBlocked);
+    }
+
+    /**
+     * Set if the shield will take durability damage or not.
+     */
+    public void setShieldTakesDamage(boolean damage)
+    {
+        this.shieldTakesDamage = damage;
+    }
+
+}