//http://en.wikipedia.org/wiki/ISO_week_date#Calculating_a_date_given_the_year.2C_week_number_and_weekday
export function dayOfYearFromWeeks(year, week, weekday, firstDayOfWeekOfYear, firstDayOfWeek) {
- var d = createUTCDate(year, 0, 1).getUTCDay();
- var daysToAdd;
- var dayOfYear;
+ var week1Jan = 6 + firstDayOfWeek - firstDayOfWeekOfYear, janX = createUTCDate(year, 0, 1 + week1Jan), d = janX.getUTCDay(), dayOfYear;
+ if (d < firstDayOfWeek) {
+ d += 7;
+ }
- d = d === 0 ? 7 : d;
- weekday = weekday != null ? weekday : firstDayOfWeek;
- daysToAdd = firstDayOfWeek - d + (d > firstDayOfWeekOfYear ? 7 : 0) - (d < firstDayOfWeek ? 7 : 0);
- dayOfYear = 7 * (week - 1) + (weekday - firstDayOfWeek) + daysToAdd + 1;
+ weekday = weekday != null ? 1 * weekday : firstDayOfWeek;
+
+ dayOfYear = 1 + week1Jan + 7 * (week - 1) - d + weekday;
return {
- year : dayOfYear > 0 ? year : year - 1,
- dayOfYear : dayOfYear > 0 ? dayOfYear : daysInYear(year - 1) + dayOfYear
+ year: dayOfYear > 0 ? year : year - 1,
+ dayOfYear: dayOfYear > 0 ? dayOfYear : daysInYear(year - 1) + dayOfYear
};
}
assert.equal(moment([2009, 11, 27]).weekYear(), 2009);
assert.equal(moment([2009, 11, 28]).weekYear(), 2010);
});
+
+// Verifies that the week number, week day computation is correct for all dow, doy combinations
+test('week year roundtrip', function (assert) {
+ var dow, doy, wd, m;
+ for (dow = 0; dow < 7; ++dow) {
+ for (doy = dow; doy < dow + 7; ++doy) {
+ for (wd = 0; wd < 7; ++wd) {
+ moment.locale('dow: ' + dow + ', doy: ' + doy, {week: {dow: dow, doy: doy}});
+ // We use the 10th week as the 1st one can spill to the previous year
+ m = moment('2015 10 ' + wd, 'gggg w d', true);
+ assert.equal(m.format('gggg w d'), '2015 10 ' + wd, 'dow: ' + dow + ' doy: ' + doy + ' wd: ' + wd);
+ m = moment('2015 10 ' + wd, 'gggg w e', true);
+ assert.equal(m.format('gggg w e'), '2015 10 ' + wd, 'dow: ' + dow + ' doy: ' + doy + ' wd: ' + wd);
+ }
+ }
+ }
+});
+
+test('week numbers 2012/2013', function (assert) {
+ moment.locale('dow: 6, doy: 12', {week: {dow: 6, doy: 12}});
+ assert.equal(52, moment('2012-12-28', 'YYYY-MM-DD').week()); // 51 -- should be 52?
+ assert.equal(1, moment('2012-12-29', 'YYYY-MM-DD').week()); // 52 -- should be 1
+ assert.equal(1, moment('2013-01-01', 'YYYY-MM-DD').week()); // 52 -- should be 1
+ assert.equal(2, moment('2013-01-08', 'YYYY-MM-DD').week()); // 53 -- should be 2
+ assert.equal(2, moment('2013-01-11', 'YYYY-MM-DD').week()); // 53 -- should be 2
+ assert.equal(3, moment('2013-01-12', 'YYYY-MM-DD').week()); // 1 -- should be 3
+ assert.equal(52, moment().weeksInYear(2012)); // 52
+});