public void GenerateEven_Should_ThrowArgumentOutOfRangeException_When_LimitIsLowerThantZero(int input)
 {
     Assert.Throws <ArgumentOutOfRangeException>(() => numbergenerator.GenerateEven(input));
 }
 public void GenerateEven_IncorrectLimitParameter_Throws_ArgumentOutOfRangeException()
 {
     Assert.Throws <ArgumentOutOfRangeException>(() => generator.GenerateEven(-1));
 }