Book Image

UI Testing with Puppeteer

By : Dario Kondratiuk
Book Image

UI Testing with Puppeteer

By: Dario Kondratiuk

Overview of this book

Puppeteer is an open source web automation library created by Google to perform tasks such as end-to-end testing, performance monitoring, and task automation with ease. Using real-world use cases, this book will take you on a pragmatic journey, helping you to learn Puppeteer and implement best practices to take your automation code to the next level! Starting with an introduction to headless browsers, this book will take you through the foundations of browser automation, showing you how far you can get using Puppeteer to automate Google Chrome and Mozilla Firefox. You’ll then learn the basics of end-to-end testing and understand how to create reliable tests. You’ll also get to grips with finding elements using CSS selectors and XPath expressions. As you progress through the chapters, the focus shifts to more advanced browser automation topics such as executing JavaScript code inside the browser. You’ll learn various use cases of Puppeteer, such as mobile devices or network speed testing, gauging your site’s performance, and using Puppeteer as a web scraping tool. By the end of this UI testing book, you’ll have learned how to make the most of Puppeteer’s API and be able to apply it in your real-world projects.
Table of Contents (12 chapters)

Debugging tests with Visual Studio Code

Many developers consider debugging a last resort. Others would flood their code with console.log messages. I consider debugging a productivity tool.

Debugging is trying to find bugs by running an application step by step.

We have two ways of launching our tests in debug mode. The first option is creating a JavaScript debug terminal from the Terminal tab. That will create a new terminal as we did before, but in this case, Visual Studio will enable the debugger when you run a command from that terminal:

Debugging from the terminal

The second option is going to the Run tab and creating a launch.json file. You could also create that file manually inside the .vscode folder:

Create a launch.json from the run tab

Once we have the file, we can create a new configuration so that we can run npm run test in the terminal:

    "version": "0.2.0",