michael@0: datediff = function(date1, date2, interval) {
michael@0:     var delta = 1;
michael@0:     switch(interval) {
michael@0:       case "day":
michael@0: 	delta /= 24;
michael@0:       case "minute":
michael@0: 	delta /= 60;
michael@0:       case Math:
michael@0: 	break;
michael@0:     }
michael@0:     return delta;
michael@0: };
michael@0: 
michael@0: var diff = datediff(new Date("2012-04-28T14:30:00Z"), new Date("2012-04-29T14:30:00Z"), "day");
michael@0: for (var i = 0; i < 50; i++) {
michael@0:     diff = datediff(new Date("2012-04-28T17:00:00Z"), new Date("2012-04-28T17:30:00Z"), "minute");
michael@0:     assertEq(diff, 1/60);
michael@0: }