diff options
Diffstat (limited to 'internal/calendar/temporal.go')
| -rw-r--r-- | internal/calendar/temporal.go | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/internal/calendar/temporal.go b/internal/calendar/temporal.go index 568efdc..b14e974 100644 --- a/internal/calendar/temporal.go +++ b/internal/calendar/temporal.go @@ -23,11 +23,15 @@ type temporalDay struct { } // adventStart returns the First Sunday of Advent that opens the liturgical year -// containing Christmas of the given calendar year: the 4th Sunday before Dec 25. +// containing Christmas of the given calendar year. The 4th Sunday of Advent is +// the Sunday on or before Christmas Eve (Dec 24) — anchoring on Dec 24, not +// Dec 25, keeps Christmas Day itself from being counted as an Advent Sunday +// (which loses a week in years when Dec 25 is a Sunday). Advent I is 3 Sundays +// earlier. func adventStart(year int) time.Time { - xmas := time.Date(year, 12, 25, 0, 0, 0, 0, time.UTC) - sun := xmas.AddDate(0, 0, -int(xmas.Weekday())) // Sunday on/before Christmas (Sunday=0) - return sun.AddDate(0, 0, -21) + eve := time.Date(year, 12, 24, 0, 0, 0, 0, time.UTC) + sun := eve.AddDate(0, 0, -int(eve.Weekday())) // 4th Sunday of Advent + return sun.AddDate(0, 0, -21) // 1st Sunday of Advent } func sameDay(a, b time.Time) bool { |