Exposing getWeekYear

src/xdate.js

@@ -303,6 +303,16 @@ proto.getUTCWeek = function() {
 };
 
 
+proto.getWeekYear = function() {
+	return _getWeekYear(curry(_getField, this, false));
+};
+
+
+proto.getUTCWeekYear = function() {
+	return _getWeekYear(curry(_getField, this, true));
+};
+
+
 proto.setWeek = function(n, year) {
 	_setWeek(this, n, year, false);
 	return this; // for chaining
@@ -339,6 +349,11 @@ function getWeek(year, month, date) {
 }
 
 
+function _getWeekYear(getField) {
+	return getWeekYear(getField(FULLYEAR), getField(MONTH), getField(DATE));
+}
+
+
 function getWeekYear(year, month, date) { // get the year that the date's week # belongs to
 	var d = new Date(UTC(year, month, date));
 	if (d < getWeek1(year)) {
@@ -590,7 +605,9 @@ function getTokenReplacement(xdate, token, getField, getSetting, useUTC) {
 		case 'zzz'  : return useUTC ? 'Z' : _getTZString(xdate, token);
 		case 'w'    : return _getWeek(getField);
 		case 'ww'   : return zeroPad(_getWeek(getField));
-		case 'S'    :
+		case 'jj'		: return (_getWeekYear(getField)+'').substring(2);
+		case 'jjjj' : return _getWeekYear(getField);
+		case 'S'    : 
 			var d = getField(DATE);
 			if (d > 10 && d < 20) return 'th';
 			return ['st', 'nd', 'rd'][d % 10 - 1] || 'th';

test/formatting.js

@@ -59,6 +59,16 @@ test("long names", function() {
 		.toString('dddd, MMMM dd, yyyy') == "Saturday, November 05, 2011";
 });
 
+test("week year, two digits", function() {
+	return new XDate(2012, 12, 31)
+		.toString('jj') == '13';
+});
+
+test("week year, four digits", function() {
+	return new XDate(2012, 12, 31)
+		.toString('jjjj') == '2013';
+});
+
 
 test("ordinals", function() {
 	return new XDate(2011, 1, 1).toString('dS') == "1st" &&

test/getters.js

@@ -69,3 +69,11 @@ test("getWeek/getUTCWeek mega-test", function() {
 	}
 	return true;
 });
+
+test("getWeekYear", function() {
+	return new XDate(2012, 12, 31).getWeekYear() == 2013;
+});
+
+test("getUTCWeekYear", function() {
+	return new XDate(2012, 12, 31, 12, 30).getUTCWeekYear() == 2013;
+});