fromString returning incorrect options given simple recurrence string

[JeffBaumgardt]

When parsing a rule string using RRule.fromString an incorrect option is being returned.

• [x] Verify that you've looked through existing issues for duplicates before creating a new one

• [x] Code sample reproducing the issue. Be sure to include all input values you are using such as the exact RRule string and dates.

• [x] Expected output

• [x] Actual output

• [x] The version of rrule you are using

• [x] Your operating system

• [ ] Your local timezone (run $ date from the command line of the machine showing the bug) - Inapplicable

• rrule version: 2.6.4

• Operating System: Windows 10

• Code Sandbox: https://codesandbox.io/s/silly-rosalind-7fwnn

When using a simple recurrence of RRULE:FREQ=WEEKLY I would expect the byweekday array in the options to be empty. However, it appears to populate with a random weekday number.

Please see console output for json objects

I have also tested with byday FREQ=WEEKLY;BYDAY=MO,TU,WE,TH,FR,SA and these are correctly listed. It's just when there is no BYDAY option in the string that's causing the issue.

[Wycza]

I encounter the same problem. When using fromString('RRULE:FREQ=WEEKLY;INTERVAL=1;WKST=MO') returned object contains byweekday: [6] which is Sunday (today day). It should not fill byweekday with any value.

[dayre]

Just discovered this today when trying to fromString a weekly rule interval 1. Workaround is to test the string prior, and add an empty array to get around the parseOptions code that adds the byweekday value.

var roptions = RRule.parseString(val)
if (val.indexOf("FREQ=WEEKLY") > 0 && val.indexOf("BYDAY") == -1) {
    roptions.byweekday = []
}
var rrule = new RRule(roptions)