public void Chain_of_Responsibility_Pattern_Test()
{
var first = new FirstStep();
var second = new SecondStep();
var third = new ThirdStep();
first.Next(second).Next(third);
Assert.IsTrue((bool)first.Handler(NumberEnum.One));
Assert.IsTrue((bool)first.Handler(NumberEnum.Two));
Assert.IsTrue((bool)first.Handler(NumberEnum.Three));
Assert.IsNull(first.Handler(NumberEnum.Four));
}
