34 lines
817 B
JavaScript
34 lines
817 B
JavaScript
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'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var $defineProperty = GetIntrinsic('%Object.defineProperty%', true);
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var hasPropertyDescriptors = function hasPropertyDescriptors() {
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if ($defineProperty) {
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try {
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$defineProperty({}, 'a', { value: 1 });
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return true;
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} catch (e) {
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// IE 8 has a broken defineProperty
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return false;
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}
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}
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return false;
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};
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hasPropertyDescriptors.hasArrayLengthDefineBug = function hasArrayLengthDefineBug() {
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// node v0.6 has a bug where array lengths can be Set but not Defined
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if (!hasPropertyDescriptors()) {
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return null;
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}
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try {
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return $defineProperty([], 'length', { value: 1 }).length !== 1;
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} catch (e) {
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// In Firefox 4-22, defining length on an array throws an exception.
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return true;
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}
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};
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module.exports = hasPropertyDescriptors;
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