PaperMC/paper-server/patches/sources/net/minecraft/world/item/FishingRodItem.java.patch

--- a/net/minecraft/world/item/FishingRodItem.java
+++ b/net/minecraft/world/item/FishingRodItem.java
@@ -14,6 +14,11 @@
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.gameevent.GameEvent;
 
+// CraftBukkit start
+import org.bukkit.event.player.PlayerFishEvent;
+import org.bukkit.craftbukkit.CraftEquipmentSlot;
+// CraftBukkit end
+
 public class FishingRodItem extends Item {
 
     public FishingRodItem(Item.Properties settings) {
@@ -26,7 +31,7 @@
 
         if (user.fishing != null) {
             if (!world.isClientSide) {
-                int i = user.fishing.retrieve(itemstack);
+                int i = user.fishing.retrieve(hand, itemstack); // Paper - Add hand parameter to PlayerFishEvent
 
                 itemstack.hurtAndBreak(i, user, LivingEntity.getSlotForHand(hand));
             }
@@ -34,13 +39,24 @@
             world.playSound((Player) null, user.getX(), user.getY(), user.getZ(), SoundEvents.FISHING_BOBBER_RETRIEVE, SoundSource.NEUTRAL, 1.0F, 0.4F / (world.getRandom().nextFloat() * 0.4F + 0.8F));
             user.gameEvent(GameEvent.ITEM_INTERACT_FINISH);
         } else {
-            world.playSound((Player) null, user.getX(), user.getY(), user.getZ(), SoundEvents.FISHING_BOBBER_THROW, SoundSource.NEUTRAL, 0.5F, 0.4F / (world.getRandom().nextFloat() * 0.4F + 0.8F));
+            // world.playSound((EntityHuman) null, entityhuman.getX(), entityhuman.getY(), entityhuman.getZ(), SoundEffects.FISHING_BOBBER_THROW, SoundCategory.NEUTRAL, 0.5F, 0.4F / (world.getRandom().nextFloat() * 0.4F + 0.8F));
             if (world instanceof ServerLevel) {
                 ServerLevel worldserver = (ServerLevel) world;
                 int j = (int) (EnchantmentHelper.getFishingTimeReduction(worldserver, itemstack, user) * 20.0F);
                 int k = EnchantmentHelper.getFishingLuckBonus(worldserver, itemstack, user);
 
-                Projectile.spawnProjectile(new FishingHook(user, world, k, j), worldserver, itemstack);
+                // CraftBukkit start
+                FishingHook entityfishinghook = new FishingHook(user, world, k, j);
+                PlayerFishEvent playerFishEvent = new PlayerFishEvent((org.bukkit.entity.Player) user.getBukkitEntity(), null, (org.bukkit.entity.FishHook) entityfishinghook.getBukkitEntity(), CraftEquipmentSlot.getHand(hand), PlayerFishEvent.State.FISHING);
+                world.getCraftServer().getPluginManager().callEvent(playerFishEvent);
+
+                if (playerFishEvent.isCancelled()) {
+                    user.fishing = null;
+                    return InteractionResult.PASS;
+                }
+                world.playSound((Player) null, user.getX(), user.getY(), user.getZ(), SoundEvents.FISHING_BOBBER_THROW, SoundSource.NEUTRAL, 0.5F, 0.4F / (world.getRandom().nextFloat() * 0.4F + 0.8F));
+                Projectile.spawnProjectile(entityfishinghook, worldserver, itemstack);
+                // CraftBukkit end
             }
 
             user.awardStat(Stats.ITEM_USED.get(this));