Function formatBest

src/type/unit/Unit.js:1195–1216

* Helper function to normalize a unit for conversion and formatting * @param {Unit} unit The unit to be normalized * @return {Object} Object with normalized unit and value * @private

(unit, options = {})

 * @private
 */
  function formatBest (unit, options = {}) {
    // Simplfy the unit list, unless it is valueless or was created directly in the
    // constructor or as the result of to or toSI
    const simp = unit.skipAutomaticSimplification || unit.value === null
      ? unit.clone()
      : unit.simplify()

    // Apply some custom logic for handling VA and VAR. The goal is to express the value of the unit as a real value, if possible. Otherwise, use a real-valued unit instead of a complex-valued one.
    handleVAandVARUnits(simp)
    // Now apply the best prefix
    // Units must have only one unit and not have the fixPrefix flag set
    applyBestPrefixIfNeeded(simp, options.offset)

    const value = simp._denormalize(simp.value)
    const valueStr = (simp.value !== null) ? format(value, options || {}) : ''
    const unitStr = simp.formatUnits()
    return {
      simp,
      valueStr,
      unitStr
    }
  }

  /**
   * Helper to handle VA and VAR units