In locales where the first weekday is a monday, the previous code
had a off by one error determining the week a sunday is in.
The problem ultimately arose because in the
`gcal_date_time_get_start_of_week()` function the variable
`n_days_after_week_start` would become negative (-1 in this case) making
the following `g_date_time_add_days (date, -n_days_after_week_start)`
add 1 day resulting in `start_of_week` being set to the start of the
following week.
The solution was to make sure `n_days_after_week_start` would be
positive by adding 7 to it. The variable is taken modulo 7 hence this
should not introduce any bugs.
Fixes#583
Right now, comparing dates with gcal_date_time_compare_date() gives
the exact opposite result of when comparing using g_date_time_compare().
As shown by this patch, this was a source of *many* bugs.
For whatever reason, libical doesn't support the Etc/UTC timezone.
Currently we crash gnome-calendar whenever libical doesn't support the
current timezone (as returned by GTimeZone). Let's fall back to UTC
instead.
Fixes#485
The return value is nullable, but gnome-calendar fails to check it.
Because the nullable return value is inconvenient for us, we can instead
add and use gcal_context_get_icaltimezone() to supplement the existing
gcal_context_get_timezone().
We'll also need a function to convert from GTimeZone to ICalTimezone,
gcal_timezone_to_icaltimezone().
Fixes#419
GNOME Calendar needs to deal with two different
weekday ranges:
1. Sunday → 0 ... Saturday → 6
2. Monday → 1 ... Sunday → 7 (used by GDateTime)
When converting (2) into (1), the correct calculation
is `weekday % 7`.
However, gcal_date_time_get_start_of_week() was doing
`weekday - 1` instead.
Fix it and do the correct calculation instead.
https://gitlab.gnome.org/GNOME/gnome-calendar/issues/451
Georges Basile Stavracas Neto