Daylight saving and add function

[ShijunK]

it seems that when hitting daylight saving, a moment object with time zone can not compute add days properly

var day = moment("2012-11-04");
console.log(day);
console.log(day.add("days",1));

//output with firefox+firebug
//Sun Nov 04 2012 00:00:00 GMT-0400 { _i="2012-11-04", _f="YYYY-MM-DD ", _isUTC=false, more...}
//Mon Nov 05 2012 00:00:00 GMT-0500 { _i="2012-11-04", _f="YYYY-MM-DD ", _isUTC=false, more...}


var dayTZ = moment("2012-11-04").tz("America/New_York");
console.log(dayTZ);
console.log(dayTZ.add("days",1));

//Sun Nov 04 2012 00:00:00 GMT-0400 { _i="2012-11-04", _f="YYYY-MM-DD ", _isUTC=true, more...}
// instead Nov 05, it returns +1 hour
//Sun Nov 04 2012 01:00:00 GMT-0400 { _i="2012-11-04", _f="YYYY-MM-DD ", _isUTC=true, more...}
// and continue +24 hours after that
Mon Nov 05 2012 01:00:00 GMT-0500 { _i="2012-11-04", _f="YYYY-MM-DD ", _isUTC=true, more...}

var dayTZ2 = moment("2012-11-01").tz("America/New_York");
console.log(dayTZ2);
console.log(dayTZ2.add("days",1));

//when not crossing daylight saving, timezone works properly
Thu Nov 01 2012 00:00:00 GMT-0400 { _i="2012-11-01", _f="YYYY-MM-DD ", _isUTC=true, more...}
//Fri Nov 02 2012 00:00:00 GMT-0400 { _i="2012-11-01", _f="YYYY-MM-DD ", _isUTC=true, more...}

with timezone-data as:

define(["moment-timezone"], function (moment) {
    moment.tz.add({
        "zones": {
            "America/Los_Angeles": [
                "-7:52:58 - LMT 1883_10_18_12_7_2 -7:52:58",
                "-8 US P%sT 1946 -8",
                "-8 CA P%sT 1967 -8",
                "-8 US P%sT"
            ],
            "America/New_York": [
                "-4:56:2 - LMT 1883_10_18_12_3_58 -4:56:2",
                "-5 US E%sT 1920 -5",
                "-5 NYC E%sT 1942 -5",
                "-5 US E%sT 1946 -5",
                "-5 NYC E%sT 1967 -5",
                "-5 US E%sT"
            ]
        },
        "rules": {
            "US": [
                "1918 1919 2 0 8 2 0 1 D",
                "1918 1919 9 0 8 2 0 0 S",
                "1942 1942 1 9 7 2 0 1 W",
                "1945 1945 7 14 7 23 1 1 P",
                "1945 1945 8 30 7 2 0 0 S",
                "1967 2006 9 0 8 2 0 0 S",
                "1967 1973 3 0 8 2 0 1 D",
                "1974 1974 0 6 7 2 0 1 D",
                "1975 1975 1 23 7 2 0 1 D",
                "1976 1986 3 0 8 2 0 1 D",
                "1987 2006 3 1 0 2 0 1 D",
                "2007 9999 2 8 0 2 0 1 D",
                "2007 9999 10 1 0 2 0 0 S"
            ],
            "CA": [
                "1948 1948 2 14 7 2 0 1 D",
                "1949 1949 0 1 7 2 0 0 S",
                "1950 1966 3 0 8 2 0 1 D",
                "1950 1961 8 0 8 2 0 0 S",
                "1962 1966 9 0 8 2 0 0 S"
            ],
            "NYC": [
                "1920 1920 2 0 8 2 0 1 D",
                "1920 1920 9 0 8 2 0 0 S",
                "1921 1966 3 0 8 2 0 1 D",
                "1921 1954 8 0 8 2 0 0 S",
                "1955 1966 9 0 8 2 0 0 S"
            ]
        },
        "links": {}
    });
});

[zgmnkv]

Seems that it's a duplicate of the previous issue #28

[timrwood]

This has been fixed with 0.1.0.

var day = moment("2012-11-04");
console.log(day.format());               // 2012-11-04T00:00:00-07:00
console.log(day.add("days",1).format()); // 2012-11-05T00:00:00-08:00

var dayTZ = moment("2012-11-04").tz("America/New_York");
console.log(dayTZ.format());               // 2012-11-04T02:00:00-05:00
console.log(dayTZ.add("days",1).format()); // 2012-11-05T02:00:00-05:00

Note also that moment("2012-11-04") is parsing into your local timezone, and then .tz("America/New_York") is changing to the America/New_York timezone. To parse into America/New_York, use moment.tz().

var dayTZ = moment.tz("2012-11-04", "America/New_York");
console.log(dayTZ.format());               // 2012-11-04T00:00:00-04:00
console.log(dayTZ.add("days",1).format()); // 2012-11-05T00:00:00-05:00