source: imaps-frontend/node_modules/es-abstract/2016/ArrayCreate.js@ 79a0317

'use strict';

var GetIntrinsic = require('get-intrinsic');

var $ArrayPrototype = GetIntrinsic('%Array.prototype%');
var $RangeError = require('es-errors/range');
var $SyntaxError = require('es-errors/syntax');
var $TypeError = require('es-errors/type');
var isInteger = require('math-intrinsics/isInteger');
var MAX_ARRAY_LENGTH = require('math-intrinsics/constants/maxArrayLength');
var $setProto = require('set-proto');

// https://262.ecma-international.org/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;
};