3 min read

Selenium

This WebDriver testing example will use Selenium and a popular Node.js testing suite. You are expected to already have Node.js installed, along with npm or yarn although the finished example project uses pnpm.

Create a Directory for the Tests

Let’s create a space to write these tests in our project. We will be using a nested directory for this example project as we will later also go over other frameworks, but typically you will only need to use one. Create the directory we will use with mkdir -p e2e-tests. The rest of this guide will assume you are inside the e2e-tests directory.

Initializing a Selenium Project

We will be using a pre-existing package.json to bootstrap this test suite because we have already chosen specific dependencies to use and want to showcase a simple working solution. The bottom of this section has a collapsed guide on how to set it up from scratch.

package.json:

{  "name": "selenium",  "version": "1.0.0",  "private": true,  "type": "module",  "scripts": {    "test": "mocha"  },  "dependencies": {    "chai": "^5.2.1",    "mocha": "^11.7.1",    "selenium-webdriver": "^4.34.0"  }}

We have a script that runs Mocha as a test framework exposed as the test command. We also have various dependencies that we will be using to run the tests. Mocha as the testing framework, Chai as the assertion library, and selenium-webdriver which is the Node.js Selenium package.

Click me if you want to see how to set a project up from scratch

If you want to install the dependencies from scratch, just run the following command.

npm
yarn

npm install mocha chai selenium-webdriver

yarn add mocha chai selenium-webdriver

I suggest also adding a "test": "mocha" item in the package.json "scripts" key so that running Mocha can be called simply with

npm
yarn

npm test

yarn test

Testing

Unlike the WebdriverIO Test Suite, Selenium does not come out of the box with a Test Suite and leaves it up to the developer to build those out. We chose Mocha, which is pretty neutral and not related to WebDrivers, so our script will need to do a bit of work to set up everything for us in the correct order. Mocha expects a testing file at test/test.js by default, so let’s create that file now.

test/test.js:

import os from 'os';import path from 'path';import { expect } from 'chai';import { spawn, spawnSync } from 'child_process';import { Builder, By, Capabilities } from 'selenium-webdriver';import { fileURLToPath } from 'url';
const __dirname = fileURLToPath(new URL('.', import.meta.url));
// create the path to the expected application binaryconst application = path.resolve(  __dirname,  '..',  '..',  'src-tauri',  'target',  'debug',  'tauri-app');
// keep track of the webdriver instance we createlet driver;
// keep track of the tauri-driver process we startlet tauriDriver;let exit = false;
before(async function () {  // set timeout to 2 minutes to allow the program to build if it needs to  this.timeout(120000);
  // ensure the app has been built  spawnSync('yarn', ['tauri', 'build', '--debug', '--no-bundle'], {    cwd: path.resolve(__dirname, '../..'),    stdio: 'inherit',    shell: true,  });
  // start tauri-driver  tauriDriver = spawn(    path.resolve(os.homedir(), '.cargo', 'bin', 'tauri-driver'),    [],    { stdio: [null, process.stdout, process.stderr] }  );  tauriDriver.on('error', (error) => {    console.error('tauri-driver error:', error);    process.exit(1);  });  tauriDriver.on('exit', (code) => {    if (!exit) {      console.error('tauri-driver exited with code:', code);      process.exit(1);    }  });
  const capabilities = new Capabilities();  capabilities.set('tauri:options', { application });  capabilities.setBrowserName('wry');
  // start the webdriver client  driver = await new Builder()    .withCapabilities(capabilities)    .usingServer('http://127.0.0.1:4444/')    .build();});
after(async function () {  // stop the webdriver session  await closeTauriDriver();});
describe('Hello Tauri', () => {  it('should be cordial', async () => {    const text = await driver.findElement(By.css('body > h1')).getText();    expect(text).to.match(/^[hH]ello/);  });
  it('should be excited', async () => {    const text = await driver.findElement(By.css('body > h1')).getText();    expect(text).to.match(/!$/);  });
  it('should be easy on the eyes', async () => {    // selenium returns color css values as rgb(r, g, b)    const text = await driver      .findElement(By.css('body'))      .getCssValue('background-color');
    const rgb = text.match(/^rgb\((?<r>\d+), (?<g>\d+), (?<b>\d+)\)$/).groups;    expect(rgb).to.have.all.keys('r', 'g', 'b');
    const luma = 0.2126 * rgb.r + 0.7152 * rgb.g + 0.0722 * rgb.b;    expect(luma).to.be.lessThan(100);  });});
async function closeTauriDriver() {  exit = true;  // kill the tauri-driver process  tauriDriver.kill();  // stop the webdriver session  await driver.quit();}
function onShutdown(fn) {  const cleanup = () => {    try {      fn();    } finally {      process.exit();    }  };
  process.on('exit', cleanup);  process.on('SIGINT', cleanup);  process.on('SIGTERM', cleanup);  process.on('SIGHUP', cleanup);  process.on('SIGBREAK', cleanup);}
onShutdown(() => {  closeTauriDriver();});

If you are familiar with JS testing frameworks, describe, it, and expect should look familiar. We also have semi-complex before() and after() callbacks to set up and teardown mocha. Lines that are not the tests themselves have comments explaining the setup and teardown code. If you were familiar with the Spec file from the WebdriverIO example, you notice a lot more code that isn’t tests, as we have to set up a few more WebDriver related items.

Running the Test Suite

Now that we are all set up with our dependencies and our test script, let’s run it!

npm
yarn

npm test

yarn test

We should see output the following output:

➜  selenium git:(main) ✗ yarn testyarn run v1.22.11$ Mocha

  Hello Tauri    ✔ should be cordial (120ms)    ✔ should be excited    ✔ should be easy on the eyes

  3 passing (588ms)
Done in 0.93s.

We can see that our Hello Tauri test suite we created with describe had all 3 items we created with it pass their tests!

With Selenium and some hooking up to a test suite, we just enabled e2e testing without modifying our Tauri application at all!

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Last updated Oct 08, 2026