Simple JavaScript benchmarking function for simple comparisons

performance.js

/**
 * A straightforward Node benchmarking script for performance testing
 * using a similar method to jsPerf.
 *
 * Usage: `node ./performance.js`
 *
 * Can support any number of tests, with optional startup and teardown.
 */

const Benchmark = require('benchmark');

let tests = {
    'RegExp#test': () => {
        /o/.test('Hello World!');
    },
    'String#indexOf': () => {
        'Hello World!'.indexOf('o') > -1;
    }
};

let onStart = () => {};
let onComplete = () => {};

doBenchmarkTesting();

function doBenchmarkTesting() {
    let suite = new Benchmark.Suite('performance', {
        'async': true,
        'queued': true,
        'onCycle': (event) => console.log(String(event.target)),
        'onComplete': () => console.log('Fastest is ' + suite.filter('fastest').map('name'))
    });

    let keyMax = Math.max(...Object.keys(tests).map(item => item.length));

    for (const key in tests) {
        if (!tests.hasOwnProperty(key)) continue;

        suite.add(key.padEnd(keyMax + 1), {
            'fn': tests[key],
            'onStart': onStart,
            'onComplete': onComplete
        });
    }

    suite.run();
}