luxon toRelative() returning different values while migrating from moment fromNow()

[Gokulkannan08]

Describe the bug Migrating from moment to luxon: In my case moment.fromNow() and luxon.DateTime.toRelative() return different value

To Reproduce

DateTime.fromISO(new Date('2023-08-07T12:54:56.886Z').toISOString()).toRelative()

returns 16 days ago

Actual vs Expected behavior As expected should be 17 days ago

moment('2023-08-07T12:54:56.886Z').fromNow()

returns 17 days ago

• Browser - latest
• Luxon version - latest
• Your timezone - "Asia/calcutta"

[icambron]

You'll need to tell us what time it was when you ran this, and what time zone that was in.

[Gokulkannan08]

Checked round 10.30 am (IST) in the morning and periodically after that timezone - "Asia/calcutta"

[diesieben07]

I cannot reproduce this with the following code:

const dummyNow = DateTime.fromISO('2023-08-25T10:30', {zone: 'Asia/Calcutta'}).toMillis();
Settings.now = () => dummyNow;
Settings.defaultZone = 'Asia/Calcutta';
Settings.defaultLocale = 'en-US';
console.log(DateTime.fromISO(new Date('2023-08-07T12:54:56.886Z').toISOString()).toRelative());

This produces "17 days ago" for me, in Node.JS 18, Chrome and Firefox.

Please provide more details for how to reproduce this issue.

[Gokulkannan08]

I have attached the screenshot below.

Luxon

Moment

[diesieben07]

Okay, so the date you're using is 2023-08-07T18:24:56 in your time zone. Since the current time in your time zone is 2023-08-27T11:33:00, 19 days and a few hours have passed. As such the report "19 days ago" is entirely accurate.

Moment.js does some funky rounding when you call fromNow instead of giving you an accurate report. In Luxon you can use the padding option of toRelative to round up to e.g. the nearest day.

[Gokulkannan08]

@diesieben07 How to round up with the nearest day using padding in toRelative()?

[diesieben07]

const padding = Duration.fromObject({days: 1}).toMillis() / 2;
const relative = DateTime.fromISO('2023-08-07T12:54:56.886Z').toRelative({ padding });