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'use strict';
var GetIntrinsic = require('get-intrinsic');
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://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; };
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