localeData weekdays should take in account weekStart

[Titoine]

Hi,

Describe the bug
When using a local with a weekStart on Monday, localData weekdays return Sunday at first.

Expected behavior
localData should return weekdays with Monday first.
https://codesandbox.io/s/confident-cache-wibqg

Information

• Day.js Version [e.g. v1.8.21]

[iamkun]

this is expected behavior. Same as moment.js

[Titoine]

Ok, fine.

[OlivierSte]

I have the same need.
Moment accepts a boolean as parameter for weekdays() to allow weekStart in locale to be taken into consideration.
Although I don't think it's implemented in dayjs as it throws an error atm when I pass true as param.

As of 2.13.0 you can pass a bool as the first parameter of the weekday functions. If true, the weekdays will be returned in locale specific order. For instance, in the Arabic locale, Saturday is the first day of the week, thus:

moment.locale('ar');
moment.weekdays(true); // lists weekdays Saturday-Friday in Arabic
moment.weekdays(true, 2); //will result in Monday in Arabic