Every X seconds cron fails with maximum call stack exceeded

[fschaeffler]

Describe the bug When defining a cron for every X seconds, I get an exception with maximum call stack exceeded.

To Reproduce

1. install croner
2. require croner
3. create a cron which should trigger every X seconds

Example:

const { Cron } = require('croner')

// works as expected
new Cron('* * * * * *', () => console.log('test every second'))

// fails with maximum call stack exceeded
new Cron('/3 * * * * *', () => console.log('test 3 seconds'))

Uncaught RangeError: Maximum call stack size exceeded
    at CronDate.findNext (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:15327)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16435)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16993)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16993)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16993)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16791)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16993)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16993)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16993)
    at CronDate.recurse (/home/flo/dev/private/trading/autotrader/node_modules/croner/dist/croner.min.cjs:1:16993)

Expected behavior There's no exception when creating this cron and it gets triggered every X seconds.

System:

• OS: Linux (Linux 6.8.0-45-generic #45-Ubuntu SMP PREEMPT_DYNAMIC Fri Aug 30 12:02:04 UTC 2024 x86_64 GNU/Linux)
• Runtime: Node.js
• Version: 18.20.4
• croner: 8.1.2

[Hexagon]

Interesting! What if you add a before /3, like `/3 *`?

[Hexagon]

Should work, but leave this open. I need to fiure out if it should be handled as a syntax error, or "just work". Call stack is not expexted behavior!

[fschaeffler]

You're totally right. Adding an asterisk before it solves the issue. Thank you for looking into it!