@Test(expected = IllegalArgumentException.class)
public void theEndMustBeEqualOrBiggerThanTheStart() {
IntraDayDate start = IntraDayDate.create(today, zero());
IntraDayDate end = IntraDayDate.create(today.plusDays(1), zero());
assertThat(end.numberOfDaysUntil(start), equalTo(1));
}
public void theEndCanBeTheSameAsTheStart() {
IntraDayDate start = IntraDayDate.create(today, zero());
assertThat(start.numberOfDaysUntil(start), equalTo(0));