Upper bound at 31-12-2498 22:59:00?

[DevJasperNL]

While trying to reproduce #73 I noticed something else: Cronos stops working past the UTC time 31-12-2498 22:59:00.

Reproduction code:

CronExpression expression = CronExpression.Parse("* * * * *");
var fromUtc = DateTime.SpecifyKind(new DateTime(2497, 12, 25), DateTimeKind.Utc);

for (var i = 0; i < 1000000; i++)
{
    var result = expression.GetNextOccurrence(fromUtc, TimeZoneInfo.Local);
    if (result == null)
    {
        throw new InvalidOperationException($"No result for input {fromUtc}");
    }
    fromUtc = result.Value;
}

Exception is thrown with message No result for input 31-12-2498 22:59:00

Not sure if this is by design, I couldn't find anything for it.
I would have expected it to continue working up to DateTime.MaxValue. It seems like it works to about 1/4 of that.

[DevJasperNL]

Just tested this in NCrontab as well. It goes all the way to DateTime.MaxValue.

[DevJasperNL]

Closing as this looks like it is by design.
Saw int MaxYear = 2499; in CronExpression

[odinserj]

The year limit was introduced to avoid looping through 9999 year for unreachable cron expressions (as they can be more difficult than 30th of February). I have another idea to solve this problem though – to set a relative limitation, and not the absolute one. For example, we can limit the GetOccurrence method to stop iterations when nothing was found within the 100 years, starting from the from date. What do you think about this solution?