Get size on disk by highest order of magnitude using recursion.

recursive_toLargestUnit.js

// From https://ponyfoo.com/articles/var-let-const
function toLargestUnit (value, unit = `MB`) {
  const units = [`MB`, `GB`, `TB`]
  const i = units.indexOf(unit)
  const nextUnit = units[i + 1]
  if (value >= 1024 && nextUnit) {
    return toLargestUnit(value / 1024, nextUnit)
  }
  return { value, unit }
}