46 lines
1.2 KiB
JavaScript
46 lines
1.2 KiB
JavaScript
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'use strict';
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var GetIntrinsic = require('../GetIntrinsic');
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var $defineProperty = GetIntrinsic('%Object.defineProperty%', true);
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if ($defineProperty) {
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try {
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$defineProperty({}, 'a', { value: 1 });
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} catch (e) {
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// IE 8 has a broken defineProperty
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$defineProperty = null;
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}
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}
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var callBound = require('../helpers/callBound');
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var $isEnumerable = callBound('Object.prototype.propertyIsEnumerable');
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// eslint-disable-next-line max-params
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module.exports = function DefineOwnProperty(IsDataDescriptor, SameValue, FromPropertyDescriptor, O, P, desc) {
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if (!$defineProperty) {
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if (!IsDataDescriptor(desc)) {
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// ES3 does not support getters/setters
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return false;
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}
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if (!desc['[[Configurable]]'] || !desc['[[Writable]]']) {
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return false;
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}
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// fallback for ES3
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if (P in O && $isEnumerable(O, P) !== !!desc['[[Enumerable]]']) {
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// a non-enumerable existing property
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return false;
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}
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// property does not exist at all, or exists but is enumerable
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var V = desc['[[Value]]'];
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// eslint-disable-next-line no-param-reassign
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O[P] = V; // will use [[Define]]
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return SameValue(O[P], V);
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}
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$defineProperty(O, P, FromPropertyDescriptor(desc));
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return true;
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};
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