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'use strict';
var GetIntrinsic = require('../GetIntrinsic');
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://www.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;
};
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