PaperMC/paper-server/nms-patches/net/minecraft/world/entity/projectile/EntityArrow.patch

--- a/net/minecraft/world/entity/projectile/EntityArrow.java
+++ b/net/minecraft/world/entity/projectile/EntityArrow.java
@@ -44,6 +44,12 @@
 import net.minecraft.world.phys.Vec3D;
 import net.minecraft.world.phys.shapes.VoxelShape;
 
+// CraftBukkit start
+import net.minecraft.world.entity.item.EntityItem;
+import org.bukkit.event.entity.EntityCombustByEntityEvent;
+import org.bukkit.event.player.PlayerPickupArrowEvent;
+// CraftBukkit end
+
 public abstract class EntityArrow extends IProjectile {
 
     private static final double ARROW_BASE_DAMAGE = 2.0D;
@@ -210,7 +216,7 @@
                 }
 
                 if (object != null && !flag) {
-                    this.a((MovingObjectPosition) object);
+                    this.preOnHit((MovingObjectPosition) object); // CraftBukkit - projectile hit event
                     this.hasImpulse = true;
                 }
 
@@ -357,7 +363,13 @@
         int k = entity.getFireTicks();
 
         if (this.isBurning() && !flag) {
-            entity.setOnFire(5);
+            // CraftBukkit start
+            EntityCombustByEntityEvent combustEvent = new EntityCombustByEntityEvent(this.getBukkitEntity(), entity.getBukkitEntity(), 5);
+            org.bukkit.Bukkit.getPluginManager().callEvent(combustEvent);
+            if (!combustEvent.isCancelled()) {
+                entity.setOnFire(combustEvent.getDuration(), false);
+            }
+            // CraftBukkit end
         }
 
         if (entity.damageEntity(damagesource, (float) i)) {
@@ -519,7 +531,22 @@
     @Override
     public void pickup(EntityHuman entityhuman) {
         if (!this.level.isClientSide && (this.inGround || this.t()) && this.shakeTime <= 0) {
-            if (this.a(entityhuman)) {
+            // CraftBukkit start
+            ItemStack itemstack = this.getItemStack();
+            if (this.pickup == PickupStatus.ALLOWED && !itemstack.isEmpty() && entityhuman.getInventory().canHold(itemstack) > 0) {
+                EntityItem item = new EntityItem(this.level, this.locX(), this.locY(), this.locZ(), itemstack);
+                PlayerPickupArrowEvent event = new PlayerPickupArrowEvent((org.bukkit.entity.Player) entityhuman.getBukkitEntity(), new org.bukkit.craftbukkit.entity.CraftItem(this.level.getServer(), this, item), (org.bukkit.entity.AbstractArrow) this.getBukkitEntity());
+                // event.setCancelled(!entityhuman.canPickUpLoot); TODO
+                this.level.getServer().getPluginManager().callEvent(event);
+
+                if (event.isCancelled()) {
+                    return;
+                }
+                itemstack = item.getItemStack();
+            }
+
+            if ((this.pickup == EntityArrow.PickupStatus.ALLOWED && entityhuman.getInventory().pickup(itemstack)) || (this.pickup == EntityArrow.PickupStatus.CREATIVE_ONLY && entityhuman.getAbilities().instabuild)) {
+                // CraftBukkit end
                 entityhuman.receive(this, 1);
                 this.die();
             }