bug#26165: date-week-day screws up prior to AD 1

[Mark H Weaver]

Zefram <address@hidden> writes:

> Looking at day of the week, via SRFI-19's date-week-day:
>
> scheme@(guile-user)> (use-modules (srfi srfi-19))
> scheme@(guile-user)> (julian-day->date 1721426 0) 
> $1 = #<date nanosecond: 0 second: 0 minute: 0 hour: 12 day: 1 month: 1 year: 
> 1 zone-offset: 0>
> scheme@(guile-user)> (date-week-day (julian-day->date 1721426 0))
> $2 = 1
> scheme@(guile-user)> (date-week-day (julian-day->date 1721425 0))
> $3 = 6
>
> The output for 0001-01-01, Monday, is correct.  The preceding day is
> actually a Sunday, but Saturday was shown.  Looking at the code, this
> bug arises for the same reason as the problem with date-year-day raised
> in bug#26151.

This is fixed by commit a58c7abd72648f77e4ede5f62a2c4e7969bb7f95 on the
stable-2.2 branch.  I'm closing this bug now, but please reopen if
appropriate.

     Thanks!
       Mark