21 lines
614 B
JavaScript
21 lines
614 B
JavaScript
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'use strict';
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module.exports = function () {
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var weakMap, x;
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if (typeof WeakMap !== 'function') return false;
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try {
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// WebKit doesn't support arguments and crashes
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weakMap = new WeakMap([[x = {}, 'one'], [{}, 'two'], [{}, 'three']]);
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} catch (e) {
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return false;
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}
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if (String(weakMap) !== '[object WeakMap]') return false;
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if (typeof weakMap.set !== 'function') return false;
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if (weakMap.set({}, 1) !== weakMap) return false;
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if (typeof weakMap.delete !== 'function') return false;
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if (typeof weakMap.has !== 'function') return false;
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if (weakMap.get(x) !== 'one') return false;
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return true;
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};
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