Program: 51587
Project: 51587
Buggy source:
public static StockItem toStockItem(ItemStack is){
  String itemInfo=is.getTypeId() + "String_Node_Str" + is.getData().getData()+ "String_Node_Str"+ is.getAmount()+ "String_Node_Str"+ is.getDurability();
  if (!is.getEnchantments().isEmpty()) {
    itemInfo+="String_Node_Str";
    for (    Map.Entry<Enchantment,Integer> ench : is.getItemMeta().getEnchants().entrySet())     itemInfo+=ench.getKey().getId() + "String_Node_Str" + ench.getValue()+ "String_Node_Str";
  }
  if (is.getType().equals(Material.ENCHANTED_BOOK)) {
    EnchantmentStorageMeta meta=(EnchantmentStorageMeta)is.getItemMeta();
    if (!meta.getStoredEnchants().isEmpty()) {
      itemInfo+="String_Node_Str";
      for (      Map.Entry<Enchantment,Integer> e : meta.getStoredEnchants().entrySet())       itemInfo+=e.getKey().getId() + "String_Node_Str" + e.getValue()+ "String_Node_Str";
    }
  }
 else   if (StockItem.isLeatherArmor(is)) {
    LeatherArmorMeta meta=(LeatherArmorMeta)is.getItemMeta();
    Color color=meta.getColor();
    itemInfo+="String_Node_Str" + color.getRed() + "String_Node_Str"+ color.getGreen()+ "String_Node_Str"+ color.getBlue();
  }
 else   if (is.getType().equals(Material.FIREWORK)) {
    itemInfo+="String_Node_Str" + StockItem.fireworkData(is);
  }
  String name=MetaTools.getName(is);
  if (!name.isEmpty())   itemInfo+="String_Node_Str" + name;
  if (is.hasItemMeta()) {
    if (is.getItemMeta().hasLore()) {
      itemInfo+="String_Node_Str";
      System.out.print(itemInfo);
      return new StockItem(itemInfo,is.getItemMeta().getLore());
    }
  }
  return new StockItem(itemInfo);
}

Fixed version (ground truth):
public static StockItem toStockItem(ItemStack is){
  String itemInfo=is.getTypeId() + "String_Node_Str" + is.getData().getData()+ "String_Node_Str"+ is.getAmount()+ "String_Node_Str"+ is.getDurability();
  if (!is.getEnchantments().isEmpty()) {
    itemInfo+="String_Node_Str";
    for (    Map.Entry<Enchantment,Integer> ench : is.getItemMeta().getEnchants().entrySet())     itemInfo+=ench.getKey().getId() + "String_Node_Str" + ench.getValue()+ "String_Node_Str";
  }
  if (is.getType().equals(Material.ENCHANTED_BOOK)) {
    EnchantmentStorageMeta meta=(EnchantmentStorageMeta)is.getItemMeta();
    if (!meta.getStoredEnchants().isEmpty()) {
      itemInfo+="String_Node_Str";
      for (      Map.Entry<Enchantment,Integer> e : meta.getStoredEnchants().entrySet())       itemInfo+=e.getKey().getId() + "String_Node_Str" + e.getValue()+ "String_Node_Str";
    }
  }
 else   if (StockItem.isLeatherArmor(is)) {
    LeatherArmorMeta meta=(LeatherArmorMeta)is.getItemMeta();
    Color color=meta.getColor();
    itemInfo+="String_Node_Str" + color.getRed() + "String_Node_Str"+ color.getGreen()+ "String_Node_Str"+ color.getBlue();
  }
 else   if (is.getType().equals(Material.FIREWORK)) {
    itemInfo+="String_Node_Str" + StockItem.fireworkData(is);
  }
  String name=MetaTools.getName(is);
  if (!name.isEmpty())   itemInfo+="String_Node_Str" + name;
  if (is.hasItemMeta()) {
    if (is.getItemMeta().hasLore()) {
      itemInfo+="String_Node_Str";
      return new StockItem(itemInfo,is.getItemMeta().getLore());
    }
  }
  return new StockItem(itemInfo);
}