20 lines
939 B
JavaScript
20 lines
939 B
JavaScript
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'use strict';
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/* eslint-disable es/no-symbol -- required for testing */
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var V8_VERSION = require('../internals/engine-v8-version');
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var fails = require('../internals/fails');
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var global = require('../internals/global');
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var $String = global.String;
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// eslint-disable-next-line es/no-object-getownpropertysymbols -- required for testing
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module.exports = !!Object.getOwnPropertySymbols && !fails(function () {
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var symbol = Symbol('symbol detection');
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// Chrome 38 Symbol has incorrect toString conversion
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// `get-own-property-symbols` polyfill symbols converted to object are not Symbol instances
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// nb: Do not call `String` directly to avoid this being optimized out to `symbol+''` which will,
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// of course, fail.
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return !$String(symbol) || !(Object(symbol) instanceof Symbol) ||
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// Chrome 38-40 symbols are not inherited from DOM collections prototypes to instances
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!Symbol.sham && V8_VERSION && V8_VERSION < 41;
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});
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