End-to-End (E2E) testing with Cypress: How it works and why it matters

End-to-End (E2E) tests ensure that a system works from start to finish, simulating real user behavior. Unlike unit and integration tests, which validate isolated parts of the code, E2E tests check the entire application, including frontend, backend, and database interactions.

What is Cypress?

Cypress is a modern and powerful E2E testing framework designed specifically for web applications. It stands out because:

• It runs tests directly in the browser, ensuring better reliability.
• It features an interactive dashboard where you can see each test step.
• It has fast execution times, as it does not rely on WebDriver.
• It includes an automatic retry mechanism, reducing flaky tests.

How does an E2E test work in Cypress?

Cypress tests are written in JavaScript or TypeScript and run directly in the browser, simulating user actions such as:

• Navigating to a page.
• Filling out forms.
• Clicking buttons.
• Validating API responses.

Example: A simple E2E test to validate user login:

Installing and setting up Cypress

To start using Cypress, follow these steps:

Install Cypress in your project:

npm install cypress --save-dev        

Open Cypress for the first time:

npx cypress open        

This will launch Cypress’s interactive UI, where you can run and debug your tests.

Conclusion

E2E testing with Cypress helps ensure that the entire application functions correctly from a user’s perspective. When properly implemented, it reduces production issues and improves the overall user experience.

Now it’s your turn! How do you use Cypress in your projects? Have you faced any challenges with E2E testing? Share your thoughts in the comments!