UNPKG

luhn-generator

Version:

A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

55 lines (49 loc) 1.04 kB
'use strict'; var GetIntrinsic = require('../GetIntrinsic'); var $EvalError = GetIntrinsic('%EvalError%'); var DayWithinYear = require('./DayWithinYear'); var InLeapYear = require('./InLeapYear'); var MonthFromTime = require('./MonthFromTime'); // https://ecma-international.org/ecma-262/5.1/#sec-15.9.1.5 module.exports = function DateFromTime(t) { var m = MonthFromTime(t); var d = DayWithinYear(t); if (m === 0) { return d + 1; } if (m === 1) { return d - 30; } var leap = InLeapYear(t); if (m === 2) { return d - 58 - leap; } if (m === 3) { return d - 89 - leap; } if (m === 4) { return d - 119 - leap; } if (m === 5) { return d - 150 - leap; } if (m === 6) { return d - 180 - leap; } if (m === 7) { return d - 211 - leap; } if (m === 8) { return d - 242 - leap; } if (m === 9) { return d - 272 - leap; } if (m === 10) { return d - 303 - leap; } if (m === 11) { return d - 333 - leap; } throw new $EvalError('Assertion failed: MonthFromTime returned an impossible value: ' + m); };