33 lines
988 B
JavaScript
33 lines
988 B
JavaScript
"use strict";
|
|
exports.getDecade = getDecade;
|
|
var _index = require("./toDate.js");
|
|
|
|
/**
|
|
* @name getDecade
|
|
* @category Decade Helpers
|
|
* @summary Get the decade of the given date.
|
|
*
|
|
* @description
|
|
* Get the decade of the given date.
|
|
*
|
|
* @typeParam DateType - The `Date` type, the function operates on. Gets inferred from passed arguments. Allows to use extensions like [`UTCDate`](https://github.com/date-fns/utc).
|
|
*
|
|
* @param date - The given date
|
|
*
|
|
* @returns The year of decade
|
|
*
|
|
* @example
|
|
* // Which decade belongs 27 November 1942?
|
|
* const result = getDecade(new Date(1942, 10, 27))
|
|
* //=> 1940
|
|
*/
|
|
function getDecade(date) {
|
|
// TODO: Switch to more technical definition in of decades that start with 1
|
|
// end with 0. I.e. 2001-2010 instead of current 2000-2009. It's a breaking
|
|
// change, so it can only be done in 4.0.
|
|
const _date = (0, _index.toDate)(date);
|
|
const year = _date.getFullYear();
|
|
const decade = Math.floor(year / 10) * 10;
|
|
return decade;
|
|
}
|