public void TestDateTimeCompare()
{
// (From MSDN) For objects A, B, and C, the following must be true:
//
// 0. By definition, any object compares greater than a null reference.
//
// 1. A.CompareTo(A) is required to return zero.
//
// 2. If A.CompareTo(B) returns zero, then B.CompareTo(A) is required to return zero.
//
// 3. If A.CompareTo(B) returns zero and B.CompareTo(C) returns zero,
// then A.CompareTo(C) is required to return zero.
//
// 4. If A.CompareTo(B) returns a value other than zero,
// then B.CompareTo(A) is required to return a value of the opposite sign.
//
// 5. If A.CompareTo(B) returns a value x that is not equal to zero,
// and B.CompareTo(C) returns a value y of the same sign as x,
// then A.CompareTo(C) is required to return a value of the same sign as x and y.
//
DateTimeRange r0 = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:11.000Z"),
DateTime.Parse("2007-07-01T06:16:11.000Z"));
DateTimeRange r0Copy1 = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:11.000Z"),
DateTime.Parse("2007-07-01T06:16:11.000Z"));
DateTimeRange r0Copy2 = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:11.000Z"),
DateTime.Parse("2007-07-01T06:16:11.000Z"));
DateTimeRange r1 = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:11.000Z").ToUniversalTime(),
DateTime.Parse("2007-07-01T06:16:11.000Z").ToUniversalTime());
Assert.AreEqual(DateTimeKind.Local, r0.Start.Kind);
Assert.AreEqual(DateTimeKind.Local, r0.End.Kind);
Assert.AreEqual(DateTimeKind.Utc, r1.Start.Kind);
Assert.AreEqual(DateTimeKind.Utc, r1.End.Kind);
Assert.Greater(r0.CompareTo(null), 0); // 0.
Assert.AreEqual(r0.CompareTo(r0), 0); // 1.
Assert.AreEqual(r1.CompareTo(r1), 0); // 1.
Assert.AreNotEqual(r0, r1);
Assert.AreNotEqual(r0.CompareTo(r1), 0);
Assert.AreNotEqual(r1.CompareTo(r0), 0);
Assert.AreEqual(Sign(r0.CompareTo(r1)), -Sign(r1.CompareTo(r0))); // 4.
Assert.AreEqual(r0.CompareTo(r0Copy1), 0);
Assert.AreEqual(r0Copy1.CompareTo(r0), 0); // 2.
Assert.AreEqual(r0.CompareTo(r0Copy2), 0);
Assert.AreEqual(r0Copy2.CompareTo(r0), 0); // 2.
Assert.AreEqual(r0Copy2.CompareTo(r0Copy1), 0); // 3.
Assert.AreEqual(r0Copy1.CompareTo(r0Copy2), 0); // 3.
// Get a basic range.
DateTimeRange rAB = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:11.000Z"),
DateTime.Parse("2007-07-01T06:16:11.000Z"));
// Get two ranges that are bigger than the basic, because of the start or end.
DateTimeRange rAPlusOneB = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:12.000Z"),
DateTime.Parse("2007-07-01T06:16:11.000Z"));
DateTimeRange rABPlusOne = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:11.000Z"),
DateTime.Parse("2007-07-01T06:16:12.000Z"));
// Do the same for the two derived ranges
// This produces 3 new ranges, because the A+1B+1 is shared
DateTimeRange rAPlusTwoB = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:13.000Z"),
DateTime.Parse("2007-07-01T06:16:11.000Z"));
DateTimeRange rAPlusOneBPlusOne = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:12.000Z"),
DateTime.Parse("2007-07-01T06:16:12.000Z"));
DateTimeRange rABPlusTwo = new DateTimeRange(
DateTime.Parse("2007-06-30T05:16:11.000Z"),
DateTime.Parse("2007-07-01T06:16:13.000Z"));
Assert.Less(rAB.CompareTo(rAPlusOneB), 0);
Assert.Less(rAB.CompareTo(rABPlusOne), 0);
Assert.Greater(rAPlusOneB.CompareTo(rAB), 0); // 3.
Assert.Greater(rABPlusOne.CompareTo(rAB), 0); // 3.
Assert.Less(rAPlusOneB.CompareTo(rAPlusOneBPlusOne), 0);
Assert.Less(rAPlusOneB.CompareTo(rAPlusTwoB), 0);
Assert.Greater(rAPlusOneBPlusOne.CompareTo(rAPlusOneB), 0); // 3.
Assert.Greater(rAPlusTwoB.CompareTo(rAPlusOneB), 0); // 3.
Assert.Less(rABPlusOne.CompareTo(rAPlusOneBPlusOne), 0);
Assert.Less(rABPlusOne.CompareTo(rABPlusTwo), 0);
Assert.Greater(rAPlusOneBPlusOne.CompareTo(rABPlusOne), 0); // 3.
Assert.Greater(rABPlusTwo.CompareTo(rABPlusOne), 0); // 3.
Assert.Less(rAB.CompareTo(rAPlusTwoB), 0); // 5.
Assert.Less(rAB.CompareTo(rAPlusOneBPlusOne), 0); // 5.
Assert.Less(rAB.CompareTo(rABPlusTwo), 0); // 5.
Assert.Greater(rAPlusTwoB.CompareTo(rAB), 0); // 3.
Assert.Greater(rAPlusOneBPlusOne.CompareTo(rAB), 0); // 3.
Assert.Greater(rABPlusTwo.CompareTo(rAB), 0); // 3.
}