Hi, I have been watching a server for quite some time, where sometimes the system time changes by a few seconds. Several times I came across a situation where one of the jobs stopped just at the moment of time change. I researched the library and found the problem:
If during the execution of the getTimeout function (https://github.com/kelektiv/node-cron/blob/master/lib/time.js#L201) between the calculation of the sendAt time and the current time, the system time moves a few seconds forward, then it can it turns out that timeout is calculated negative and the job will stop with this line (https://github.com/kelektiv/node-cron/blob/master/lib/job.js#L190).

I created a pr in my repository fork, in which, using the synon, I simulated the time change at the right moment. My job starts every 5 seconds and I move the time 7 seconds forward, after which the job stops.
https://github.com/psixdev/node-cron/pull/1/files

I understand that an accidental change in the time on the server is an unlikely event, but I believe that the problem really exists and it is serious. I suppose a similar bug can occur during the transition to daylight saving time (or vice versa), if this transition accidentally coincides with the call to the getTImeout function.

What do you think about this problem?