1543658 - Missing rounding mode in internal UNumberFormat in Intl.PluralRules?

Status: RESOLVED FIXED

(Core :: JavaScript: Internationalization API, defect, P2)

Description

[André Bargull [:anba]]

new Intl.PluralRules("en", {maximumFractionDigits:0}).select(0.5) currently returns "other". But given that new Intl.NumberFormat("en", {maximumFractionDigits:0}).format(0.5) returns "1", is the correct result actually "one"?

Also compare, new Intl.PluralRules("en", {maximumFractionDigits:0}).select(0) returns "other", whereas new Intl.PluralRules("en", {maximumFractionDigits:0}).select(1) returns "one".

https://tc39.github.io/ecma402/#sec-pluralruleselect doesn't describe if n or operands should be used to select the correct plural representation:

When the PluralRuleSelect abstract operation is called with four arguments, it performs an implementation-dependent algorithm to map n to the appropriate plural representation of the Plural Rules Operands Record operands by selecting the rules denoted by type for the corresponding locale, or the String value "other".

Comment 1

[Zibi Braniecki [:zbraniecki][:gandalf]]

So, seems like we respect minimumFractionDigits, but not maximumFractionDigits? :)

new Intl.PluralRules("en", {minimumFractionDigits:0}).select(1) // one
new Intl.PluralRules("en", {minimumFractionDigits:1}).select(1) // other

I'd say we should respect maximum as well.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The priority flag is not set for this bug.
:Waldo, could you have a look please?

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Comment 3

[Jeff Walden [:Waldo]]

Yeah, I'm inclined to say we should be doing round-to-nearest-even everywhere. PluralRules delegates a bunch of stuff to NumberFormat handling already, and this seems like the sort of thing where the algorithm should be following suit.

Comment 4

[André Bargull [:anba]]

Attachment: Bug 1543658: Add missing rounding-mode to Intl.PluralRules. r=jwalden!

Comment 5

[André Bargull [:anba]]

Try: https://treeherder.mozilla.org/#/jobs?repo=try&revision=427b008b06263ea278b38a8b40bfd359e34d1436

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/79e15e776159
Add missing rounding-mode to Intl.PluralRules. r=jwalden

Comment 7

[Andrei Ciure[:aciure]]

https://hg.mozilla.org/mozilla-central/rev/79e15e776159

Comment 8

[BugBot [:suhaib / :marco/ :calixte]]

Since the status are different for nightly and release, what's the status for beta?
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