my-idlers/node_modules/es5-ext/date/#/days-in-month.js

"use strict";

var getMonth = Date.prototype.getMonth;

module.exports = function () {
	switch (getMonth.call(this)) {
		case 1:
			return this.getFullYear() % 4 ? 28 : 29;
		case 3:
		case 5:
		case 8:
		case 10:
			return 30;
		default:
			return 31;
	}
};