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fix(common): include minutes in the short GMT timezone format #69239

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fix(common): include minutes in the short GMT timezone format #69239

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16 changes: 13 additions & 3 deletions packages/common/src/i18n/format_date.ts
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Original file line number Diff line number Diff line change
Expand Up @@ -458,7 +458,7 @@ function getDateTranslation(

/**
* Returns a date formatter that transforms a date and an offset into a timezone with ISO8601 or
* GMT format depending on the width (eg: short = +0430, short:GMT = GMT+4, long = GMT+04:30,
* GMT format depending on the width (eg: short = +0430, short:GMT = GMT+4:30, long = GMT+04:30,
* extended = +04:30)
*/
function timeZoneGetter(width: ZoneWidth): DateFormatter {
Expand All @@ -473,8 +473,18 @@ function timeZoneGetter(width: ZoneWidth): DateFormatter {
padNumber(hours, 2, minusSign) +
padNumber(Math.abs(zone % 60), 2, minusSign)
);
case ZoneWidth.ShortGMT:
return 'GMT' + (zone >= 0 ? '+' : '') + padNumber(hours, 1, minusSign);
case ZoneWidth.ShortGMT: {
// The short localized GMT format omits a leading zero on the hours but,
// per CLDR, still includes the minutes when they are non-zero (e.g.
// `GMT+5:30` for India, `GMT-4` for New York).
const minutes = Math.abs(zone % 60);
return (
'GMT' +
(zone >= 0 ? '+' : '') +
padNumber(hours, 1, minusSign) +
(minutes ? ':' + padNumber(minutes, 2, minusSign) : '')
);
}
Comment on lines +476 to +487

@JeanMeche JeanMeche Jun 8, 2026

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Is that true for every locale ? (the CLDR is a funny rabbithole)

@erkamyaman erkamyaman Jun 8, 2026

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Good question, it is a bit of a rabbit hole indeed. No, the full format isn't identical across locales. I checked Intl short offsets for a +5:30 zone:

  • most locales (en, de, ja, hi, tr, …): GMT+5:30
  • fr: UTC+5:30 (UTC, not GMT)
  • fi: UTC+5.30 (UTC and a . separator)
  • ar: غرينتش+5:30 (translated label)
  • fa: ‎+۵:۳۰ گرینویچ (Persian digits, label after the offset, RTL)

So the literal, separator, digits and order are all locale-dependent. What is universal is that the minutes are kept when they're non-zero, and that's the only thing this change touches.

timeZoneGetter already renders a locale-independent GMT±H[:mm] for every locale (same as the Long/Extended widths), so this doesn't add locale divergence, it just stops the short form dropping the minutes the long form already keeps.

I can reword the code comment to call that out if you think it's worth it.

@JeanMeche JeanMeche Jun 8, 2026

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My point is more : This is not worth fixing and users should rely on Intl if they want top-tier date i18n.

@erkamyaman erkamyaman Jun 8, 2026

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It makes sense, agreed that Intl is the right call for proper date i18n. I'll close this out. Thanks for the look, I appreciate it.

case ZoneWidth.Long:
return (
'GMT' +
Expand Down
2 changes: 1 addition & 1 deletion packages/common/src/pipes/date_pipe.ts
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Expand Up @@ -174,7 +174,7 @@ export const DATE_PIPE_DEFAULT_OPTIONS = new InjectionToken<DatePipeConfig>(
* | Zone | z, zz & zzz | Short specific non location format (fallback to O) | GMT-8 |
* | | zzzz | Long specific non location format (fallback to OOOO) | GMT-08:00 |
* | | Z, ZZ & ZZZ | ISO8601 basic format | -0800 |
* | | ZZZZ | Long localized GMT format | GMT-8:00 |
* | | ZZZZ | Long localized GMT format | GMT-08:00 |
* | | ZZZZZ | ISO8601 extended format + Z indicator for offset 0 (= XXXXX) | -08:00 |
* | | O, OO & OOO | Short localized GMT format | GMT-8 |
* | | OOOO | Long localized GMT format | GMT-08:00 |
Expand Down
29 changes: 20 additions & 9 deletions packages/common/test/i18n/format_date_spec.ts
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Expand Up @@ -287,24 +287,28 @@ describe('Format date', () => {

it('should format with timezones', () => {
const dateFixtures: any = {
z: /GMT(\+|-)\d/,
zz: /GMT(\+|-)\d/,
zzz: /GMT(\+|-)\d/,
z: /GMT(\+|-)\d\:30/,
zz: /GMT(\+|-)\d\:30/,
zzz: /GMT(\+|-)\d\:30/,
zzzz: /GMT(\+|-)\d{2}\:30/,
Z: /(\+|-)\d{2}30/,
ZZ: /(\+|-)\d{2}30/,
ZZZ: /(\+|-)\d{2}30/,
ZZZZ: /GMT(\+|-)\d{2}\:30/,
ZZZZZ: /(\+|-)\d{2}\:30/,
O: /GMT(\+|-)\d/,
O: /GMT(\+|-)\d\:30/,
OOOO: /GMT(\+|-)\d{2}\:30/,
};

Object.keys(dateFixtures).forEach((pattern: string) => {
expect(formatDate(date, pattern, ɵDEFAULT_LOCALE_ID, '+0430')).toMatch(
dateFixtures[pattern],
);
});
// Both a positive and a negative fractional offset, so the short GMT
// format is exercised for each sign with non-zero minutes.
for (const offset of ['+0430', '-0330']) {
Object.keys(dateFixtures).forEach((pattern: string) => {
expect(formatDate(date, pattern, ɵDEFAULT_LOCALE_ID, offset)).toMatch(
dateFixtures[pattern],
);
});
}
});

it('should format common multi component patterns', () => {
Expand Down Expand Up @@ -528,6 +532,13 @@ describe('Format date', () => {
const dateEst = formatDate(isoDate, 'long', 'en', 'EST');
expect(dateEst).toBe('February 17, 2024, 7:00:00 AM GMT-5');

// Short GMT (`O`) keeps non-zero minutes for fractional zones, drops them
// for whole-hour zones, for both signs.
expect(formatDate(isoDate, 'O', 'en', '+0530')).toBe('GMT+5:30');
expect(formatDate(isoDate, 'O', 'en', '+0545')).toBe('GMT+5:45');
expect(formatDate(isoDate, 'O', 'en', '-0330')).toBe('GMT-3:30');
expect(formatDate(isoDate, 'O', 'en', '-0500')).toBe('GMT-5');

const dateOffset = formatDate(isoDate, 'long', 'en', '+0500');
expect(dateOffset).toBe('February 17, 2024, 5:00:00 PM GMT+5');
});
Expand Down
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