Intl.DateTimeFormat timezone polyfill

Surgically polyfills timezone support in Intl.DateTimeFormat API

Some browsers do not support arbitrary time zone in Intl.DateTimeFormat API (becuase its optional as per ECMA-402 standard). This polyfill is only to bring this support. Polyfill contains historical timezone data, CLDR data & tiny code to polyfill this support.

How to use?

1. Install via nodejs:

npm i date-time-format-timezone

And then import in your code:

require('date-time-format-timezone'); // polyfill is ready

2. In the browser

include everything:

<script src="https://unpkg.com/date-time-format-timezone@latest/build/browserified/date-time-format-timezone-complete-min.js">

or include individual files:

<script src="https://unpkg.com/date-time-format-timezone@latest/build/browserified/date-time-format-timezone-no-data-min.js">
<script src="https://unpkg.com/date-time-format-timezone@latest/build/browserified/data/locales/locale-en-US-POSIX.js">
<script src="https://unpkg.com/date-time-format-timezone@latest/build/browserified/data/metazone.js">
<script src="https://unpkg.com/date-time-format-timezone@latest/build/browserified/data/timezones/tzdata-america-los_angeles.js">

This polyfill can add this support.

new Intl.DateTimeFormat('hi', {
    timeZone: 'Asia/Calcutta',
    timeZoneName:'long',
    year: 'numeric',
    month: 'numeric',
    day: 'numeric',
    hour: 'numeric',
    minute: 'numeric',
}).format(new Date());

"११/१/२०१७, पू १:२६ भारतीय मानक समय"


new Intl.DateTimeFormat('en', {
    timeZone: 'America/Los_Angeles',
    timeZoneName:'long',
    year: 'numeric',
    month: 'numeric',
    day: 'numeric',
    hour: 'numeric',
    minute: 'numeric',
}).format(new Date());

"1/10/2017, 12:00 PM Pacific Standard Time"

Support

API	Support
Intl.DateTimeFormat	✅
Date.toLocaleString	✅
Date.toLocaleTimeString	✅
Date.toLocaleTimeString	✅

Generate latest data from www.iana.org.

git checkout https://github.com/yahoo/date-time-format-timezone.git
npm install
grunt download
grunt
npm publish

Browserified file size

	Minified	gzipped
complete	2.64MB	322KB
top zones1 only no locale	369.32KB	71KB
all zones no locale	303.19KB	75KB
top zones1 top locale2	641.86KB	148KB

*1. top zones are custom listed timezones here.

*2. top locales are custom listed locales here.

References

1. http://www.unicode.org/reports/tr35/tr35-dates.html#Using_Time_Zone_Names
2. http://icu-project.org/apiref/icu4j/com/ibm/icu/text/TimeZoneNames.html