Add support for dateStyle and timeStyle for Android

[dlebedynskyi]

Problem

Intl on Android is still missing dateStyle and timeStyle. iOS already has it since v0.12.

Solution

Ask is to add support for missing Intl.DateTimeFormat API for Android dateStyle/timeStyle.

Additional Context

If possible, would be great to add rest of missing API

• dayPeriod
• fractionalSecondDigits

to close rest of missing options on Intl.DateTimeFormat as polyfill for Intl.DateTimeFormat is complex and heavy, and is currently required when dateStyle/timeStyle are used.

Related #23 (comment)

[mganandraj]

I've created a PR : #927

@neildhar

[dlebedynskyi]

@mganandraj we did some local testing with your PR.
It looks like weekday: 'narrow' is still missing (spec). Any chance you can add it as well?

[mganandraj]

Hi @dlebedynskyi, weekday: 'narrow' is implemented .. Do you have a specific test case that fails ?

[dlebedynskyi]

@mganandraj sorry for late reply.

We think there is a bug in how it is implemented.

The way it is done, it does not match the spec - https://tc39.es/ecma402/#datetimeformat-objects.

`If required is "date" or "any", then
a. For each property name prop of « "weekday", "year", "month", "day" », do
i. Let value be ? Get(options, prop).
ii. If value is not undefined, let needDefaults be false.

as example

const date = new Date(Date.UTC(2012, 11, 20, 3, 0, 0, 200));
// request a weekday along with a long date
let options = {
  weekday: "narrow"
};
console.log(new Intl.DateTimeFormat("en-US", options).format(date)); 
// outputs "W, 12/19/2012" which is wrong,

this should just be "W" since using "weekday" negates the need for defaults.

Fix that we tested was here in https://github.com/facebook/hermes/blob/main/lib/VM/JSLib/Intl.cpp#L272

- {u"weekday", platform_intl::Option::Kind::String, 0},
+ {u"weekday", platform_intl::Option::Kind::String, kDateRequired},

We had tested your change prior it was merged, and took time to find fix.
So maybe we can do PR now or you can some testing. I can also open separate issue if needed. WDYT?

[mganandraj]

Hello @dlebedynskyi .. 100% agreed. This bug has existed from day 1 and somehow left unnoticed. We do run most relevant Test262 test cases which doesn't seem to cover this.

I'd appreciate if you can send a PR.

[nandorojo]

Hey all, would you recommend that we use #927 as a patch in our app? Or is there likelihood of this getting merged soon?

[neildhar]

Hey @nandorojo, it looks like this was already merged in a72115f, and is present in RN 0.73. Closing this issue.