next() and prev() are not symmetrical; prev() is skipping a day that next() includes.

Expected Behavior

A call to next() is symmetrical with a call to prev().

Actual Behavior

A call to next() produces Sat whereas a call to prev() skips Sat and instead produces Fri.

var cronParser = require("cron-parser")

const options = {
    currentDate: new Date("Tue 03 Jan 2017 00:00:00 UTC"),
    utc: true
};
 
const interval = cronParser.parseExpression("0 30 15 * * 1-6", options);

console.log(interval.prev().toDate().toUTCString()); // Mon 
console.log(interval.prev().toDate().toUTCString()); // Fri
console.log(interval.next().toDate().toUTCString()); // Sat
console.log(interval.next().toDate().toUTCString()); // Mon
console.log(interval.prev().toDate().toUTCString()); // Fri

https://runkit.com/5912594388e92a00122cb663/5912594388e92a00122cb664

[santigimeno]

I think https://github.com/harrisiirak/cron-parser/pull/101 should fix this.

[faazshift]

@harrisiirak @santigimeno I’ve meant to work on this, but life has been pretty hectic. To me this bug still seems to exist, both on master and on #99. I’ll try to dig into this sometime this week.