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

86 lines (78 loc) 2.67 kB
'use strict'; var GetIntrinsic = require('../GetIntrinsic'); var $RangeError = GetIntrinsic('%RangeError%'); var $TypeError = GetIntrinsic('%TypeError%'); var assign = require('object.assign'); var isPropertyDescriptor = require('../helpers/isPropertyDescriptor'); var IsArray = require('./IsArray'); var IsAccessorDescriptor = require('./IsAccessorDescriptor'); var IsDataDescriptor = require('./IsDataDescriptor'); var OrdinaryDefineOwnProperty = require('./OrdinaryDefineOwnProperty'); var OrdinaryGetOwnProperty = require('./OrdinaryGetOwnProperty'); var ToNumber = require('./ToNumber'); var ToString = require('./ToString'); var ToUint32 = require('./ToUint32'); var Type = require('./Type'); // https://www.ecma-international.org/ecma-262/6.0/#sec-arraysetlength // eslint-disable-next-line max-statements, max-lines-per-function module.exports = function ArraySetLength(A, Desc) { if (!IsArray(A)) { throw new $TypeError('Assertion failed: A must be an Array'); } if (!isPropertyDescriptor({ Type: Type, IsDataDescriptor: IsDataDescriptor, IsAccessorDescriptor: IsAccessorDescriptor }, Desc)) { throw new $TypeError('Assertion failed: Desc must be a Property Descriptor'); } if (!('[[Value]]' in Desc)) { return OrdinaryDefineOwnProperty(A, 'length', Desc); } var newLenDesc = assign({}, Desc); var newLen = ToUint32(Desc['[[Value]]']); var numberLen = ToNumber(Desc['[[Value]]']); if (newLen !== numberLen) { throw new $RangeError('Invalid array length'); } newLenDesc['[[Value]]'] = newLen; var oldLenDesc = OrdinaryGetOwnProperty(A, 'length'); if (!IsDataDescriptor(oldLenDesc)) { throw new $TypeError('Assertion failed: an array had a non-data descriptor on `length`'); } var oldLen = oldLenDesc['[[Value]]']; if (newLen >= oldLen) { return OrdinaryDefineOwnProperty(A, 'length', newLenDesc); } if (!oldLenDesc['[[Writable]]']) { return false; } var newWritable; if (!('[[Writable]]' in newLenDesc) || newLenDesc['[[Writable]]']) { newWritable = true; } else { newWritable = false; newLenDesc['[[Writable]]'] = true; } var succeeded = OrdinaryDefineOwnProperty(A, 'length', newLenDesc); if (!succeeded) { return false; } while (newLen < oldLen) { oldLen -= 1; // eslint-disable-next-line no-param-reassign var deleteSucceeded = delete A[ToString(oldLen)]; if (!deleteSucceeded) { newLenDesc['[[Value]]'] = oldLen + 1; if (!newWritable) { newLenDesc['[[Writable]]'] = false; OrdinaryDefineOwnProperty(A, 'length', newLenDesc); return false; } } } if (!newWritable) { return OrdinaryDefineOwnProperty(A, 'length', { '[[Writable]]': false }); } return true; };