zonedTimeToUtc is not working for timeZone Etc/GMT+6

[zitniak]

zonedTimeToUtc('2019-11-26T10:00:00', 'America/Chicago'); // returns correct 2019-11-26T16:00:00.000Z

zonedTimeToUtc('2019-11-26T10:00:00', 'Etc/GMT+6'); // returns incorrect 2019-11-26T10:00:000Z, timezone Etc/GMT+6 is silently ignored. Nor Unsupported time zone specified is thrown. It should return too 2019-11-26T16:00:00.000Z. It's Central Standard Time (CST).

Etc/GMT+6 is correct timezone identification by IANA database https://en.wikipedia.org/wiki/List_of_tz_database_time_zones

findTimeZone('Etc/GMT+6') from require('timezone-support') confirming that timezone exists.

zonedTimeToUtc is not working generally with timezones 'Etc/GMT+X'.

Versions:
date-fns-tz: v.1.0.8
date-fns: v.2.8.1

[marnusw]

findTimeZone('Etc/GMT-6') from require('timezone-support') confirming that timezone exists.

Please see if you can get this time zone to work with Intl.DateTimeFormat directly on the platform(s) you are targeting. If that fails then there is nothing to be done in date-fns-tz at the moment because it simply uses Intl.DateTimeFormat without any other checks.

date-fns: v.1.30.1

This library was designed for use with date-fns v2. There is no guarantee it will work as expected with v1. (Although that does not seem to be the issue in this particular case.)

[zitniak]

Thanks, sorry I am using date-fns:"2.8.1" (I wrongly copy-pasted the version, I fixed my description).

I've tried:

var date = new Date(Date.UTC(2019, 11, 26, 10, 0, 0));
var expectedResult = Intl.DateTimeFormat(undefined, {
    'Etc/GMT+6'
}).format(date);

It throws the error: RangeError: Expected Area/Location(/Location)* for time zone, got Etc/GMT+6

Now I believe the zonedTimeToUtc should throw at least an error too, because the error is hidden.

BTW Moment.js handles moment.tz('2019-11-26T10:00:00', 'Etc/GMT+6') correctly, it returns 2019-11-26T16:00:00.000Z

[nilamsavani]

Facing same problem. Any solution?

[NellyHayrapetyan]

findTimeZone('Etc/GMT-6') from require('timezone-support') confirming that timezone exists.

Please see if you can get this time zone to work with Intl.DateTimeFormat directly on the platform(s) you are targeting. If that fails then there is nothing to be done in date-fns-tz at the moment because it simply uses Intl.DateTimeFormat without any other checks.

date-fns: v.1.30.1

This library was designed for use with date-fns v2. There is no guarantee it will work as expected with v1. (Although that does not seem to be the issue in this particular case.)

@marnusw I tried to do this utcToZonedTime(1581509131067, 'Etc/GMT-6'))
It returns Wed Feb 12 2020 12:05:31 (ignoring the given timezone),

Here is the Intl.DateTimeFormat implementation

Intl.DateTimeFormat(undefined, {
      year: 'numeric',
      month: 'numeric',
      day: 'numeric',
      hour: 'numeric',
      minute: 'numeric',
      second: 'numeric',
      timeZone: 'Etc/GMT-6',
    }).format(1581509131067)

which understands the timezone and returns 2/12/2020, 6:05:31 PM

[Pustelto]

This actually seems like problem with tzParseTimezone function. I have tried to check it's regexp pattern for timezoneIANA and it is not picking up the Etc.