private void ValidateNewPizza(Pizza pizza)
{
Pizzas.ToList().ForEach(p => {
new Validator <Pizza>(pizza)
.Ensure(!pizza.IsSimilarTo(p), $"A pizza \"{pizza}\" já existe nesse pedido!")
.Run();
});
}
public IReadOnlyCollection <Pizza> GetPizzas()
{
return(new ReadOnlyCollection <Pizza>(Pizzas.ToList()));
}