react-native/Libraries/Utilities/RCTRenderingPerf.js

81 lines
1.9 KiB
JavaScript

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*
* @providesModule RCTRenderingPerf
* @flow
*/
'use strict';
var ReactDefaultPerf = require('ReactDefaultPerf');
var ReactPerf = require('ReactPerf');
var invariant = require('invariant');
type perfModule = {
start: () => void;
stop: () => void;
}
var perfModules = [];
var enabled = false;
var RCTRenderingPerf = {
// Once perf is enabled, it stays enabled
toggle: function() {
console.log('Render perfomance measurements enabled');
enabled = true;
},
start: function() {
if (!enabled) {
return;
}
ReactDefaultPerf.start();
perfModules.forEach((module) => module.start());
},
stop: function() {
if (!enabled) {
return;
}
ReactDefaultPerf.stop();
ReactDefaultPerf.printInclusive();
ReactDefaultPerf.printWasted();
var totalRender = 0;
var totalTime = 0;
var measurements = ReactDefaultPerf.getLastMeasurements();
for (var ii = 0; ii < measurements.length; ii++) {
var render = measurements[ii].render;
for (var nodeName in render) {
totalRender += render[nodeName];
}
totalTime += measurements[ii].totalTime;
}
console.log('Total time spent in render(): ' + totalRender + 'ms');
perfModules.forEach((module) => module.stop());
},
register: function(module: perfModule) {
invariant(
typeof module.start === 'function',
'Perf module should have start() function'
);
invariant(
typeof module.stop === 'function',
'Perf module should have stop() function'
);
perfModules.push(module);
}
};
module.exports = RCTRenderingPerf;