Program: 27635
Project: 27635
Buggy source:
@Overwrite public int handleHookRetraction(){
  ItemStack itemStack=null;
  int exp=0;
  if (this.ticksCatchable > 0) {
    itemStack=this.func_146033_f();
    exp=this.rand.nextInt(6) + 1;
  }
  PlayerRetractFishingLineEvent event=SpongeEventFactory.createPlayerRetractFishingLineEvent(SpongeMod.instance.getGame(),(Player)this.angler,this,(org.spongepowered.api.item.inventory.ItemStack)itemStack,(org.spongepowered.api.entity.Entity)this.caughtEntity,exp);
  byte b0=0;
  if (!SpongeMod.instance.getGame().getEventManager().post(event)) {
    exp=(int)event.getExp();
    if (event.getCaughtEntity().isPresent()) {
      this.caughtEntity=(Entity)event.getCaughtEntity().get();
      double entityitem=this.angler.posX - this.posX;
      double d2=this.angler.posY - this.posY;
      double d4=this.angler.posZ - this.posZ;
      double d6=MathHelper.sqrt_double(entityitem * entityitem + d2 * d2 + d4 * d4);
      double d8=0.1D;
      this.caughtEntity.motionX+=entityitem * d8;
      this.caughtEntity.motionY+=d2 * d8 + MathHelper.sqrt_double(d6) * 0.08D;
      this.caughtEntity.motionZ+=d4 * d8;
      b0=3;
    }
    if (event.getCaughtItem().isPresent()) {
      EntityItem entityitem1=new EntityItem(this.worldObj,this.posX,this.posY,this.posZ,(ItemStack)event.getCaughtItem().get());
      double d1=this.angler.posX - this.posX;
      double d3=this.angler.posY - this.posY;
      double d5=this.angler.posZ - this.posZ;
      double d7=MathHelper.sqrt_double(d1 * d1 + d3 * d3 + d5 * d5);
      double d9=0.1D;
      entityitem1.motionX=d1 * d9;
      entityitem1.motionY=d3 * d9 + MathHelper.sqrt_double(d7) * 0.08D;
      entityitem1.motionZ=d5 * d9;
      this.worldObj.spawnEntityInWorld(entityitem1);
      this.angler.worldObj.spawnEntityInWorld(new EntityXPOrb(this.angler.worldObj,this.angler.posX,this.angler.posY + 0.5D,this.angler.posZ + 0.5D,this.rand.nextInt(6) + 1));
      b0=1;
    }
    if (this.inGround) {
      b0=2;
    }
    this.setDead();
    this.angler.fishEntity=null;
    if (this.fishingRod != null) {
      this.fishingRod.damageItem(b0,this.angler);
      this.angler.swingItem();
      this.fishingRod=null;
    }
  }
  return b0;
}

Fixed version (ground truth):
@Overwrite public int handleHookRetraction(){
  ItemStack itemStack=null;
  int exp=0;
  if (this.ticksCatchable > 0) {
    itemStack=this.func_146033_f();
    exp=this.rand.nextInt(6) + 1;
  }
  PlayerRetractFishingLineEvent event=SpongeEventFactory.createPlayerRetractFishingLineEvent(SpongeMod.instance.getGame(),(Player)this.angler,this,(org.spongepowered.api.item.inventory.ItemStack)itemStack,(org.spongepowered.api.entity.Entity)this.caughtEntity,exp);
  byte b0=0;
  if (!SpongeMod.instance.getGame().getEventManager().post(event)) {
    exp=event.getExp();
    if (event.getCaughtEntity().isPresent()) {
      this.caughtEntity=(Entity)event.getCaughtEntity().get();
      double entityitem=this.angler.posX - this.posX;
      double d2=this.angler.posY - this.posY;
      double d4=this.angler.posZ - this.posZ;
      double d6=MathHelper.sqrt_double(entityitem * entityitem + d2 * d2 + d4 * d4);
      double d8=0.1D;
      this.caughtEntity.motionX+=entityitem * d8;
      this.caughtEntity.motionY+=d2 * d8 + MathHelper.sqrt_double(d6) * 0.08D;
      this.caughtEntity.motionZ+=d4 * d8;
      b0=3;
    }
    if (event.getCaughtItem().isPresent()) {
      EntityItem entityitem1=new EntityItem(this.worldObj,this.posX,this.posY,this.posZ,(ItemStack)event.getCaughtItem().get());
      double d1=this.angler.posX - this.posX;
      double d3=this.angler.posY - this.posY;
      double d5=this.angler.posZ - this.posZ;
      double d7=MathHelper.sqrt_double(d1 * d1 + d3 * d3 + d5 * d5);
      double d9=0.1D;
      entityitem1.motionX=d1 * d9;
      entityitem1.motionY=d3 * d9 + MathHelper.sqrt_double(d7) * 0.08D;
      entityitem1.motionZ=d5 * d9;
      this.worldObj.spawnEntityInWorld(entityitem1);
      this.angler.worldObj.spawnEntityInWorld(new EntityXPOrb(this.angler.worldObj,this.angler.posX,this.angler.posY + 0.5D,this.angler.posZ + 0.5D,this.rand.nextInt(6) + 1));
      b0=1;
    }
    if (this.inGround) {
      b0=2;
    }
    this.setDead();
    this.angler.fishEntity=null;
    if (this.fishingRod != null) {
      this.fishingRod.damageItem(b0,this.angler);
      this.angler.swingItem();
      this.fishingRod=null;
    }
  }
  return b0;
}