31 lines
719 B
JavaScript
31 lines
719 B
JavaScript
'use strict';
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/**
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* Copyright (c) 2013-present, Facebook, Inc.
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*
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* This source code is licensed under the MIT license found in the
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* LICENSE file in the root directory of this source tree.
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*
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* @typechecks
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*/
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var performance = require('./performance');
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var performanceNow;
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/**
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* Detect if we can use `window.performance.now()` and gracefully fallback to
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* `Date.now()` if it doesn't exist. We need to support Firefox < 15 for now
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* because of Facebook's testing infrastructure.
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*/
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if (performance.now) {
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performanceNow = function performanceNow() {
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return performance.now();
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};
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} else {
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performanceNow = function performanceNow() {
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return Date.now();
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};
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}
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module.exports = performanceNow; |