Measure tests time in code signal

code-signal-measure-tests.js

/**
* This script is used to run measurements on CodeSignal https://app.codesignal.com
* to use it simply open the dev tools, and paste in the console, 
* it will automate the browser for you to run the tests and measure the times it took.
* be patient, there are measurements to prevent blocking from CodeSignal, 
* and this script just automates the browser which means it cannot run tests in parallel
* so the tests will take a while, just run this and go grab a coffee.
* 
* !!!CAUTION!!! this isn't an official script and might get you banned from CodeSignal 
* even though there are measurements to try and prevent this, use caution.
*
* ***NOTICE*** by no means this tool is accurate, but it's a good way to know 
* if there is a big difference in the implementations you made for the same test
*
* Some slow computers will need to adjust the timeToWaitWhenObservingButtonTextChange number.
**/

// set this to define how many times to run the tests
const runTestsXTimes = 3; 
// these can change depending on language settings
const buttonIdentifier = '.run-button';
const buttonReadyText = 'Run tests';
const buttonRunningText = 'Running tests';
// wait 5-10 seconds between tests, prevents blocking
// set to 0 if you don't wish to wait
const timeToWaitBetweenTests = () => 5000 + (Math.random() * 5000)
// usually should be 0, on slower computers maybe around 5 or 10 milliseconds?
// the highest this number is, the lest accurate the measurement
const timeToWaitWhenObservingButtonTextChange = 0;
// -----------------------------------------------

const measureSingleTest = (id) => {
  return new Promise((resolve) => {
    const buttonWrapper = document.querySelector(buttonIdentifier);
    const btn = document.querySelector(`${buttonIdentifier} [role="button"]`);
    let started = 0;
    let finished = 0;
    // we don't use request animation frame, 
    // since this should run as fast as possible and not wait for the frame to update
    const myInterval = setInterval(() => {
      if (!started && buttonWrapper.textContent === buttonRunningText) {
        started = Date.now();
      }
      if (started && buttonWrapper.textContent === buttonReadyText) {
        finished = Date.now();
        clearInterval(myInterval);
        const time = finished - started;
        resolve(time);
        console.log(`test ${id} took ~ ${time} milliseconds`)
      }
    }, timeToWaitWhenObservingButtonTextChange);
    btn.click();
  })
}

// helper functions
const wait = (time) => new Promise(resolve => setTimeout(resolve, time));
const average = numbers => numbers.reduce((acc, n) => acc + n, 0) / numbers.length;
const median = numbers => numbers.slice().sort((a, b) => a - b)[Math.floor(numbers.length / 2)];

const runMeasurements = async (times) => {
  console.log('running tests....');
  const measurements = [];
  for (let i = 0; i < times; i++) {
    const timeTook = await measureSingleTest(i);
    measurements.push(timeTook);
    if(i !== times - 1) {
      // this wait line is not required, 
      // it's here to prevent getting banned for automation
      await wait(timeToWaitBetweenTests());
    }
  }
  console.log('------ Tests Report ------');
  console.log(`average: ${average(measurements)}`);
  console.log(`median: ${median(measurements)}`);
  console.log(`low: ${Math.min(...measurements)}`);
  console.log(`high: ${Math.max(...measurements)}`);
  console.log(`run: ${measurements.length} tests`);
  console.log(`measurements:`, measurements);
  console.log('------ ------ ------ ------');
}

// run the tests X times
runMeasurements(runTestsXTimes);