E2E Testing Using Cypress

Walter Code
6 min readNov 16, 2023

Embarking on the ever-evolving journey of web development, we recently navigated the intricate world of load balancing algorithms in our blog “Demystifying Load Balancing Algorithms: An Intermediate Guide.”

Today, we shift our focus to another critical facet of the digital realm — software testing, with a particular emphasis on End-to-End (E2E) testing. This exploration is a natural continuation of our previous discussion, as both load balancing and testing stand as essential pillars for achieving optimal performance, scalability, and reliability in web applications.

Introduction to E2E Testing

End-to-end (E2E) testing is a software testing methodology that evaluates the complete functionality of a software application from start to finish. The goal of E2E testing is to ensure that all components of a system are working together as expected and that the application behaves as intended in a real-world environment.

In E2E testing, the entire application workflow is tested, simulating the user’s interaction with the software. This type of testing is typically conducted in a production-like environment and may involve multiple subsystems or components. The purpose is to identify and address any issues related to the integration of various system components and to ensure that the application performs as expected in a real-world scenario.

E2E testing can be automated or performed manually. Automated E2E testing involves using testing tools and scripts to simulate user interactions and verify that the application functions correctly. This automation helps in repeating tests efficiently, especially when new code changes are introduced.

Importance of E2E testing in software development

End-to-End (E2E) testing is essential in software development for several reasons. It simulates real-world scenarios, ensuring a positive user experience by testing the entire application from the user’s perspective. E2E testing identifies integration issues, detects defects early in the development cycle, and provides comprehensive test coverage, including regression testing.

End to End Testing

It fosters collaboration between teams, contributes to a culture of quality, and enhances the overall reliability and stability of the software. By delivering a high-quality product, E2E testing ultimately contributes to customer satisfaction by reducing the likelihood of critical issues impacting end-users.

Challenges in manual E2E testing

Manual End-to-End (E2E) testing poses challenges such as time consumption, susceptibility to human error, resource intensiveness, limited scalability, repetitive tasks leading to tester fatigue, inconsistency in execution, incomplete coverage of scenarios, difficulty in bug reproduction, and associated costs.

The manual testing process is hindered by its inability to efficiently execute tests in parallel and struggles with scalability for complex applications. While human intuition is valuable, combining automated testing with manual approaches can help address these challenges by improving efficiency, reliability, and overall test coverage in software development.

What is Cypress?

Introduction to Cypress as a JavaScript-based E2E testing framework

Cypress is a powerful JavaScript-based End-to-End (E2E) testing framework designed for modern web applications. It stands out for its developer-friendly approach, ease of use, and capabilities that enable efficient testing of web applications. Cypress is built on JavaScript and utilizes its ecosystem, making it accessible to a broad audience of developers. One notable feature is its ability to perform in-browser testing, providing a real-time view of the application under test.

Cypress supports a range of browsers and offers a comprehensive set of commands for interacting with web elements, making it well-suited for simulating user interactions and ensuring the functionality and performance of web applications. With a robust set of features, including automatic waiting, time-travel debugging, and a simple setup process, Cypress has gained popularity as a preferred choice for E2E testing in JavaScript-based web development projects.

Key features of Cypress

Cypress, a JavaScript-based End-to-End (E2E) testing framework, boasts a developer-friendly syntax, real-time browser testing, and automatic waiting, enhancing test reliability and ease of use. Notable features include time-travel debugging for effective issue identification, cross-browser support ensuring consistency, and fast test execution, crucial for continuous integration.

Cypress provides comprehensive logging and reporting, supports parallel test execution, and offers built-in capabilities for mocking and stubbing network requests. Its interactive test runner facilitates real-time feedback, while fixture data and custom commands contribute to test readability and reusability. Continuously developed with a strong community, Cypress remains a powerful and efficient choice for testing JavaScript-based web applications.

Before Cypress / With Cypress

What makes Cypress different?

Cypress does not use Selenium

Most end-to-end testing tools are Selenium-based, which is why they all share the same problems. To make Cypress different, we built a new architecture from the ground up. Whereas Selenium executes remote commands through the network, Cypress runs in the same run-loop as your application.

Cypress focuses on doing end-to-end testing REALLY well

Cypress is not a general automation framework, nor is it a unit testing framework for your back-end services. There are already great tools out there that do that. Rather, we specialize in one thing — creating a great experience while you write end-to-end tests for your web applications.

Cypress works on any front-end framework or website

Cypress tests anything that runs in a web browser. All of the architecture surrounding Cypress is built to handle modern JavaScript frameworks especially well. We have hundreds of projects using the latest React, Angular, Vue, Elm, etc. frameworks. Cypress also works equally well on older server-rendered pages or applications.

Cypress tests are only written in JavaScript

While you can compile down to JavaScript from any other language, ultimately the test code is executed inside the browser itself. There are no language or driver bindings — there is and will only ever be JavaScript.

Cypress is all in one

Writing end-to-end tests takes a lot of different tools to work together. With Cypress, you get multiple tools in one. There is no need to install 10 separate tools and libraries to get your test suite setup. We have taken some of the best-in-class tools you are likely already familiar with and made them all work together seamlessly.

Cypress is for developers and QA engineers

Cypress is for developers and QA engineers. One of our goals was to make test-driven development a reality for end-to-end testing. Cypress is at its best when you use it as you build your application. We give you the power to code as fast as possible.

Cypress vs Selenium

Cypress and Selenium are popular web testing tools with distinct characteristics. Cypress operates directly in the browser, offering real-time testing, faster execution, and automatic waiting, primarily supporting JavaScript. In contrast, Selenium follows a client-server architecture, supporting multiple languages and browsers. While Cypress excels in speed, ease of use, and built-in parallel execution, Selenium boasts broader browser support, a mature ecosystem, and extensive community resources.

The choice between them depends on factors like language preference, testing requirements, and project needs, with Cypress favored for simplicity and speed, and Selenium for its versatility and established community support.

Conclusion

In conclusion, End-to-End (E2E) testing is a critical methodology in software development, ensuring comprehensive evaluation of application functionality. Cypress, as a JavaScript-based E2E testing framework, stands out for its developer-friendly approach, real-time browser testing, and features like automatic waiting and time-travel debugging. E2E testing, whether automated or manual, plays a vital role in detecting integration issues and ensuring a high-quality, reliable software product.

While Cypress excels in speed and simplicity, its comparison with Selenium highlights the trade-offs between the two tools, emphasizing factors such as language preference and testing requirements in the decision-making process for web testing frameworks. Ultimately, the choice between Cypress and Selenium depends on project needs, with both tools offering valuable features for effective E2E testing in the dynamic landscape of web development.

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