public void ToXml_DaysPastDueLessThanOrEqualTo()
{
SubscriptionSearchRequest request = new SubscriptionSearchRequest().DaysPastDue.LessThanOrEqualTo(4);
var xml = "<search><days-past-due><max>4</max></days-past-due></search>";
Assert.AreEqual(xml, request.ToXml());
}