[Bug]: Cron validator

[kyungjun-pe]

What happened?

Hello.

I was testing cron expressions using this library.

I encountered an error with the following schedules, which are semantically equivalent:

The schedule 10 0-3,9-23 * * * is correct.

The schedule 10 9-23,0-3 * * * is incorrect.

I don't understand why this library is generating this error.

I'm also curious if it's intentional.

Version

v10

Example Code

type CronStruct struct {
  Cron string `validate:"cron"`
}

err = Valid.Struct(CronStruct)

[thejus-r]

Both are valid cron expressions right?, Link this site says its valid, and seems right.
I think the issue is with the regex, how it handles "-", ranges

// regexes.go
cronRegexString = `(@(annually|yearly|monthly|weekly|daily|hourly|reboot))|(@every (\d+(ns|us|µs|ms|s|m|h))+)|((((\d+,)+\d+|((\*|\d+)(\/|-)\d+)|\d+|\*) ?){5,7})`

[kyungjun-pe]

Yes, Its same cron expressions.

However, this lib says that the format below is incorrect.

[thejus-r]

There was a similar issue, #1130, I think the issue with cron expressions is its stateful. for example 10 0-3,9-23 * * * is valid, but 10 3-0,9-23 * * * is not valid. as range should be increasing. i we have to be 100% accurate then we may need to parse it like in robfig/cron