2005702 - Treat islamic-rgsa as an unknown calendar identifier

Status: RESOLVED FIXED

(Core :: JavaScript: Internationalization API, defect, P3)

Description

[Henri Sivonen (:hsivonen)]

The islamic-rgsa identifier for Saudi Arabia sighting was added to CLDR on Oracle's request as part of the process of adopting (a subset of) Joda-Time into the Java standard library. OpenJDK (and most derivatives?) ended up shipping only islamic-umalqura (civil-use Saudi Arabia-official astronomical simulation) and, in the docs, acknowledging the possibility of past-data-only calendars, which clearly suggests viewing islamic-rgsa as such in contrast to islamic-umalqura.

None of CLDR, ICU4C, ICU4J, or ICU4X has past sighting data, but when islamic-rgsa has been requested, ICU4C has returned a calendar instance for an undocumented simulation, which has been accidentally exposed to the Web due to failure to investigate the ICU4C internals properly on this point to realize that there is no distinct islamic-rgsa back end in ICU4C.

Per the December 2025 TG2 meeting, we should treat islamic-rgsa like we treat unknown calendar identifiers. That is, -u-ca-islamic-rgsa and -u-ca-example should result in the same Web-visible behavior.

(An HTTP Archive search indicated that islamic-rgsa is not used on the Web.)

Comment 1

[André Bargull [:anba]]

If islamic-rgsa gets completely ignored for Intl.DateTimeFormat, do we still need to support it for Intl.DisplayNames? If we don't need to support it at all, we could strip the localisations from the ICU data file. See also https://github.com/tc39/proposal-intl-era-monthcode/issues/91.

js> new Intl.DisplayNames("en", {type: "calendar"}).of("islamic-rgsa")
"Hijri Calendar (Saudi Arabia, sighting)"

ICU data filter expression: -/Types/calendar/islamic-rgsa for "lang_tree".

And if complete islamic-rgsa support gets pulled, we could also consider removing the ICU formatter data. (Only used for the non-standard mozIntl.DisplayNames.):

js> var mozIntl = {}; addIntlExtras(mozIntl);                                                                        
js> new mozIntl.DisplayNames("en-u-ca-islamic-rgsa", {type: "month"}).of(1)                                           
"Muharram"

ICU data filter expression: -/calendar/islamic-rgsa for "locales_tree" and probably also -/calendarData/islamic-rgsa from "supplementalData".

Comment 2

[Henri Sivonen (:hsivonen)]

(In reply to André Bargull [:anba] from comment #1)

If islamic-rgsa gets completely ignored for Intl.DateTimeFormat, do we still need to support it for Intl.DisplayNames?

I think we don't need to support in DisplayNames. It's not used and it's not implemented. The identifier exists only because a project had multi-venue dependencies and something was anticipated and requested and not reverted when left unused. (We have the same risk of multiple moving parts and some level of uncertainty about what the entirety will be once fully baked with pieces of Temporal being split across ECMA and Unicode.)

If we don't need to support it at all, we could strip the localisations from the ICU data file.

That makes sense and would be good for binary size.

Comment 3

[Henri Sivonen (:hsivonen)]

FWIW, it turns out that Safari and Chrome already don't ship a display name for islamic-rgsa.

Comment 4

[Henri Sivonen (:hsivonen)]

(In reply to Henri Sivonen (:hsivonen) from comment #3)

FWIW, it turns out that Safari and Chrome already don't ship a display name for islamic-rgsa.

Oops. I was testing French in Safari and Chrome but English in Firefox, and it appears that there's bug in the French data. They do currently ship the display name in e.g English and Finnish. (And the Finnish string is arguably incorrectly translated.)

Comment 5

[André Bargull [:anba]]

Attachment: Bug 2005702 - Part 1: Treat 'islamic-rgsa' as an unknown calendar identifier. r=#spidermonkey-reviewers!

Comment 6

[André Bargull [:anba]]

Attachment: Bug 2005702 - Part 2: Remove 'islamic-rgsa' from ICU data file. r=#spidermonkey-reviewers!

Reduces the ICU data file size by 3056 bytes.

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/18c381348fcc
https://hg.mozilla.org/integration/autoland/rev/fa32f0cef636
Part 1: Treat 'islamic-rgsa' as an unknown calendar identifier. r=spidermonkey-reviewers,dminor
https://github.com/mozilla-firefox/firefox/commit/4d4614dca75f
https://hg.mozilla.org/integration/autoland/rev/0c018f709b8f
Part 2: Remove 'islamic-rgsa' from ICU data file. r=spidermonkey-reviewers,dminor

Comment 8

[pstanciu]

https://hg.mozilla.org/mozilla-central/rev/fa32f0cef636
https://hg.mozilla.org/mozilla-central/rev/0c018f709b8f