1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253 |
- 'use strict';
- var GetIntrinsic = require('get-intrinsic');
- var $ArrayPrototype = GetIntrinsic('%Array.prototype%');
- var $RangeError = GetIntrinsic('%RangeError%');
- var $SyntaxError = GetIntrinsic('%SyntaxError%');
- var $TypeError = GetIntrinsic('%TypeError%');
- var IsInteger = require('./IsInteger');
- var MAX_ARRAY_LENGTH = Math.pow(2, 32) - 1;
- var $setProto = GetIntrinsic('%Object.setPrototypeOf%', true) || (
- // eslint-disable-next-line no-proto, no-negated-condition
- [].__proto__ !== $ArrayPrototype
- ? null
- : function (O, proto) {
- O.__proto__ = proto; // eslint-disable-line no-proto, no-param-reassign
- return O;
- }
- );
- // https://ecma-international.org/ecma-262/6.0/#sec-arraycreate
- module.exports = function ArrayCreate(length) {
- if (!IsInteger(length) || length < 0) {
- throw new $TypeError('Assertion failed: `length` must be an integer Number >= 0');
- }
- if (length > MAX_ARRAY_LENGTH) {
- throw new $RangeError('length is greater than (2**32 - 1)');
- }
- var proto = arguments.length > 1 ? arguments[1] : $ArrayPrototype;
- var A = []; // steps 5 - 7, and 9
- if (proto !== $ArrayPrototype) { // step 8
- if (!$setProto) {
- throw new $SyntaxError('ArrayCreate: a `proto` argument that is not `Array.prototype` is not supported in an environment that does not support setting the [[Prototype]]');
- }
- $setProto(A, proto);
- }
- if (length !== 0) { // bypasses the need for step 2
- A.length = length;
- }
- /* step 10, the above as a shortcut for the below
- OrdinaryDefineOwnProperty(A, 'length', {
- '[[Configurable]]': false,
- '[[Enumerable]]': false,
- '[[Value]]': length,
- '[[Writable]]': true
- });
- */
- return A;
- };
|