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Relative Time

Locale#relativeTime should be an object of the replacement strings for dayjs#from.

This requires the UpdateLocale plugin to work

dayjs.extend(updateLocale)

dayjs.updateLocale('en', {
  relativeTime: {
    future: "in %s",
    past: "%s ago",
    s: 'a few seconds',
    m: "a minute",
    mm: "%d minutes",
    h: "an hour",
    hh: "%d hours",
    d: "a day",
    dd: "%d days",
    M: "a month",
    MM: "%d months",
    y: "a year",
    yy: "%d years"
  }
})

Locale#relativeTime.future refers to the prefix/suffix for future dates. Locale#relativeTime.past refers to the prefix/suffix for past dates.

For all others, a single character refers to the singular, and a double character refers to the plural.

Additional token processing

If a locale requires additional processing for a token, it can set the token as a function with the following signature instead of a string. The function should return a string.

relativeTime: {
  ...,
  yy: function (number, withoutSuffix, key, isFuture) {
    return string;
  }
}

The number argument refers to the number of units for that key. For m, the number is the number of minutes, etc.

The withoutSuffix argument will be true if the token will be displayed without a suffix, and false if it will be displayed with a suffix. (The reason for the inverted logic is because the default behavior is to display with the suffix.)

The key argument refers to the replacement key in the Locale#relativeTime object. (eg. s m mm h, etc.)

The isFuture argument will be true if it is going to use the future suffix/prefix and false if it is going to use the past prefix/suffix.

Relative Time thresholds and rounding

You can pass a config object while using this plugin to update its thresholds and rounding config.

var config = {
  thresholds: [{}],
  rounding: function
}
dayjs.extend(relativeTime, config)

thresholds is an Array of Object defined when a unit is considered a minute, an hour and so on. For example, by default more than 45 seconds is considered a minute, more than 22 hours is considered a day and so on. To change those you can pass a new thresholds like this.

// strict thresholds
var thresholds = [
  { l: 's', r: 1 },
  { l: 'm', r: 1 },
  { l: 'mm', r: 59, d: 'minute' },
  { l: 'h', r: 1 },
  { l: 'hh', r: 23, d: 'hour' },
  { l: 'd', r: 1 },
  { l: 'dd', r: 29, d: 'day' },
  { l: 'M', r: 1 },
  { l: 'MM', r: 11, d: 'month' },
  { l: 'y', r: 1 },
  { l: 'yy', d: 'year' }
]

You can also add your own thresholds key and update locale accordingly.

var thresholds = [
  ...,
  { l: 'ss', r: 59, d: 'second' }
]
dayjs.updateLocale('en', {
  relativeTime: {
    ...,
    ss: "%d seconds"
  }
})

rounding is an Function to process the number before supplying it to the relativeTime format string specified in the locale. To change those you can pass a new rounding like this.

// Math.round by default
var rounding = Math.floor