/** function that takes month number and its year and returns the number of days within it * @param monthNumber. * @param year. e.g.: mahfoudh.arous@gmail.com -> true e.g.: mahfoudh.arous.com ->false */ const getMonthDays = (monthNumber, year) => { const the31DaysMonths = [1, 3, 5, 7, 8, 10, 12] const the30DaysMonths = [4, 6, 9, 11] if (!the31DaysMonths.includes(monthNumber) && !the30DaysMonths.includes(monthNumber) && (monthNumber !== 2) ) { throw new TypeError('Invalid Month Number.') } if (the31DaysMonths.includes(monthNumber)) { return 31 } if (the30DaysMonths.includes(monthNumber)) { return 30 } // Check for Leap year if (year % 4 === 0) { if ((year % 100 !== 0) || (year % 100 === 0 && year % 400 === 0)) { return 29 } } return 28 } export { getMonthDays }