uppy/packages/@uppy/utils/src/prettyETA.js

const secondsToTime = require('./secondsToTime')

module.exports = function prettyETA (seconds) {
  const time = secondsToTime(seconds)

  // Only display hours and minutes if they are greater than 0 but always
  // display minutes if hours is being displayed
  // Display a leading zero if the there is a preceding unit: 1m 05s, but 5s
  const hoursStr = time.hours ? time.hours + 'h ' : ''
  const minutesVal = time.hours ? ('0' + time.minutes).substr(-2) : time.minutes
  const minutesStr = minutesVal ? minutesVal + 'm ' : ''
  const secondsVal = minutesVal ? ('0' + time.seconds).substr(-2) : time.seconds
  const secondsStr = secondsVal + 's'

  return `${hoursStr}${minutesStr}${secondsStr}`
}