47 lines
1.3 KiB
JavaScript
47 lines
1.3 KiB
JavaScript
'use strict';
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var GetIntrinsic = require('../GetIntrinsic');
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var $Array = GetIntrinsic('%Array%');
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var $species = GetIntrinsic('%Symbol.species%', true);
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var $TypeError = GetIntrinsic('%TypeError%');
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var Get = require('./Get');
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var IsArray = require('./IsArray');
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var IsConstructor = require('./IsConstructor');
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var IsInteger = require('./IsInteger');
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var Type = require('./Type');
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// https://ecma-international.org/ecma-262/6.0/#sec-arrayspeciescreate
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module.exports = function ArraySpeciesCreate(originalArray, length) {
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if (!IsInteger(length) || length < 0) {
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throw new $TypeError('Assertion failed: length must be an integer >= 0');
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}
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var len = length === 0 ? 0 : length;
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var C;
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var isArray = IsArray(originalArray);
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if (isArray) {
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C = Get(originalArray, 'constructor');
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// TODO: figure out how to make a cross-realm normal Array, a same-realm Array
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// if (IsConstructor(C)) {
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// if C is another realm's Array, C = undefined
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// Object.getPrototypeOf(Object.getPrototypeOf(Object.getPrototypeOf(Array))) === null ?
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// }
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if ($species && Type(C) === 'Object') {
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C = Get(C, $species);
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if (C === null) {
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C = void 0;
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}
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}
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}
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if (typeof C === 'undefined') {
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return $Array(len);
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}
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if (!IsConstructor(C)) {
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throw new $TypeError('C must be a constructor');
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}
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return new C(len); // Construct(C, len);
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};
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