var parse = require('../parse/index.js')
|
|
/**
|
* @category Year Helpers
|
* @summary Get the number of calendar years between the given dates.
|
*
|
* @description
|
* Get the number of calendar years between the given dates.
|
*
|
* @param {Date|String|Number} dateLeft - the later date
|
* @param {Date|String|Number} dateRight - the earlier date
|
* @returns {Number} the number of calendar years
|
*
|
* @example
|
* // How many calendar years are between 31 December 2013 and 11 February 2015?
|
* var result = differenceInCalendarYears(
|
* new Date(2015, 1, 11),
|
* new Date(2013, 11, 31)
|
* )
|
* //=> 2
|
*/
|
function differenceInCalendarYears (dirtyDateLeft, dirtyDateRight) {
|
var dateLeft = parse(dirtyDateLeft)
|
var dateRight = parse(dirtyDateRight)
|
|
return dateLeft.getFullYear() - dateRight.getFullYear()
|
}
|
|
module.exports = differenceInCalendarYears
|
