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