22 lines
621 B
JavaScript
22 lines
621 B
JavaScript
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"use strict";
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module.exports = function () {
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var weakMap, obj;
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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([[obj = {}, "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(obj) !== "one") return false;
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return true;
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};
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