Displaying time relative to a given using luxon library - luxon

Question

Does luxon support feature for Displaying time relative to a given?
Moment has "Calendar time" feature:
https://momentjs.com/docs/#/displaying/calendar-time/
moment().calendar(null, {
sameDay: '[Today]',
nextDay: '[Tomorrow]',
nextWeek: 'dddd',
lastDay: '[Yesterday]',
lastWeek: '[Last] dddd',
sameElse: 'DD/MM/YYYY'
});
Could I achieve same using luxon?

Answer 1

From version 1.9.0 you can use toRelativeCalendar:
Returns a string representation this date relative to today, such as "yesterday" or "next month" platform supports Intl.RelativeDateFormat.
const DateTime = luxon.DateTime;
const now = DateTime.local();
// Some test values
[ now,
now.plus({days: 1}),
now.plus({days: 4}),
now.minus({days: 1}),
now.minus({days: 4}),
now.minus({days: 20}),
].forEach((k) => {
console.log( k.toRelativeCalendar() );
});
<script src="https://cdn.jsdelivr.net/npm/luxon#1.10.0/build/global/luxon.js"></script>
Before version 1.9.0, there was no calendar() equivalent in Luxon.
The For Moment users manual page stated in the DateTime method equivalence => Output => Humanization section:
Luxon doesn't support these, and won't until the Relative Time Format proposal lands in browsers.
Operation | Moment | Luxon
---------------------------------------------------------------------------------------
"Calendar time" | calendar() | None (before 1.9.0) / toRelativeCalendar() (after 1.9.0)
If you need, you can write something by yourself, here a custom function example that has a similar output of moment's calendar():
const DateTime = luxon.DateTime;
function getCalendarFormat(myDateTime, now) {
var diff = myDateTime.diff(now.startOf("day"), 'days').as('days');
return diff < -6 ? 'sameElse' :
diff < -1 ? 'lastWeek' :
diff < 0 ? 'lastDay' :
diff < 1 ? 'sameDay' :
diff < 2 ? 'nextDay' :
diff < 7 ? 'nextWeek' : 'sameElse';
}
function myCalendar(dt1, dt2, obj){
const format = getCalendarFormat(dt1, dt2) || 'sameElse';
return dt1.toFormat(obj[format]);
}
const now = DateTime.local();
const fmtObj = {
sameDay: "'Today'",
nextDay: "'Tomorrow'",
nextWeek: 'EEEE',
lastDay: "'Yesterday'",
lastWeek: "'Last' EEEE",
sameElse: 'dd/MM/yyyy'
};
// Some test values
[ now,
now.plus({days: 1}),
now.plus({days: 4}),
now.minus({days: 1}),
now.minus({days: 4}),
now.minus({days: 20}),
].forEach((k) => {
console.log( myCalendar(now, k, fmtObj) );
});
<script src="https://cdn.jsdelivr.net/npm/luxon#1.8.2/build/global/luxon.js"></script>
This code roughly inspired from moment code, it can be definitely improved.