Incorrect "yesterday" examples

[mathiasbynens]

The README contains several examples that result in "yesterday", e.g.

let rtf = new Intl.RelativeTimeFormat("en");

// Format relative time using the day unit.
rtf.format(-1, "day");
// > "yesterday"

(search for "yesterday" to find them all)

However, it seems like in the default case, "1 day ago" is returned instead of "yesterday" for this and other examples.

To get the result of "yesterday", the numeric: 'auto' setting is needed.

const rtf = new Intl.RelativeTimeFormat('en', { numeric: 'auto' });
rtf.format(-1, 'day');
// > 'yesterday'

This is verified by this particular Test262 test: https://github.com/tc39/test262/blob/a81cc4213b85461b6fbca1e50abd5cfb6b21ff54/implementation-contributed/v8/intl/relative-time-format/format-en.js#L120

There are two things to do here:

• Document the numeric option in the README (currently, it's not mentioned at all)
• Update the examples in the README

[littledan]

Oops, thanks. PRs welcome!

[mathiasbynens]

FWIW, I documented numeric: 'auto' as part of https://developers.google.com/web/updates/2018/10/intl-relativetimeformat. Feel free to quote that doc if it's helpful.

[romulocintra]

Hi @littledan I'am preparing a PR based on Readme based on work done by @mathiasbynens , to have it aligned with code samples and documentation for MDN

[romulocintra]

I'am not sure if its a behaviour or defect :

rtf.format( -0,"day"  );  //  0 days ago 
rtf.format( 0,"day"  );   //  in 0 days

[rxaviers]

It's a behavior, but your question shows all developers will also be confused about it.

In practice, it's pointless to use numeric style for 0 values. You would want to see "Today" in your example instead, but in order to use "Today" correctly you need to take care of #14. Therefore, it's important to realize Intl.RelativeTimeFormat is a low level building block (at least at this point) that enables higher level abstractions such as moment.js and https://github.com/rxaviers/relative-time (used by PayPal, and by Mozilla).

[caiolima]

Is there anything missing to close this issue after #98 landed?