Technical Tutorial to Speed Up Cypress Test Suite Execution

Cypress stands as a titan in the domain of web browser testing due to its automation capabilities. Yet, as with many testing tools, challenges arise, especially when test cycles take longer than anticipated.

This comprehensive Cypress tutorial will guide you through standard and advanced approaches to enhance test suite execution times and demonstrate how to seamlessly incorporate Cypress with Launchable for optimal results.

Standard Techniques to Boost Cypress Execution

Just as the foundation of a building is crucial for its stability, understanding and implementing basic Cypress optimization techniques can profoundly impact your testing times. Here’s how to get started

• Leverage the Power of Cypress Dashboard for Parallelization: Parallelize your test runs across multiple machines with Cypress Dashboard. This can drastically reduce your test suite's execution time.

Example Configuration:

// In your cypress.json configuration file
{  "projectId": "your-project-id",  "record": true,  "parallel": true,  "group": "your-group-name" }

Note: Make sure to set up your CI environment to run multiple machines or containers concurrently.

• Segment Your Test Scenarios: Segment tests into smaller, pinpointed scenarios, reducing complexity and enhancing speed. Smaller tests also offer ease in debugging and maintenance

• Mocking API Requests: Eliminate the wait time for actual API responses by using ‘cy.intercept()’ to mock them. This significantly accelerates test execution.

Example:

cy.intercept('GET', '/api/users', { fixture: 'users.json' });

• Optimize Page Load Times: Speed is of the essence, especially when testing. Ensure your web application loads swiftly by optimizing its components. This can lead to expedited test execution.

Example:

// Opt to visit only necessary pages during tests
cy.visit('/essential-page');

Advanced Techniques for Swift Cypress Test Cycles (with Code Samples)

• Limited Use of ‘cy.wait()’: Avoid needless delays and improve the efficiency of your tests by using cy.wait() prudently.

Example:

// Instead of:
cy.wait(5000); // waits 5 seconds
// Use:
cy.get('element-selector', { timeout: 5000 }); // waits up to 5 seconds for the element

• Wise Usage of Hooks: Reducing repetitive tasks in hooks can be a game-changer for your test runtime.

• Embrace the Headless Mode: Running tests without visualizing them in the browser can enhance speed since resources aren't spent on rendering the UI.

Example:

npx cypress run --headless

• Managing Cypress Cache: Harness Cypress cache commands to optimize startup times by proficiently handling cached assets.

Example:

npx cypress cache clear npx cypress cache list

How To Speed Up Cypress With Launchable

Despite the prowess of Cypress, the real magic happens when you incorporate Launchable's Predictive Test Selection. 

With Launchable, quickly find and verify test issues. Save time, reduce costs, and ensure every test run counts. Every time tests run, your changes and test results are passed to Launchable to continuously train a model.

During model training, the system analyzes the alterations linked to each build and identifies tests that encountered failures. It establishes connections between modified files and tests that commonly exhibit failures. This process can be likened to an advanced frequency counting algorithm, effectively mapping associations between failures and the corresponding source code changes.

Execute only the most vital tests based on the recent code changes, shortening wait times and enabling quicker releases.

• Setup Launchable CLI: Ensure you have the Launchable CLI set up in your CI pipeline.

• Intelligent Test Selection: Launchable's intelligence is derived from your historical test results and code changes. To utilize this, run:

launchable record tests --name <BUILD NAME> cypress <PATH TO TEST RESULTS>

• Shift Left Your Tests:  Intelligently run a subset of Cypress tests on every pull request, providing earlier feedback and speeding up release processes. By integrating these practices and tools, you can achieve faster, more efficient Cypress testing.

Cypress Tutorial Takeaways

Harnessing Cypress Efficiently: At the heart of accelerated test cycles lies a deep understanding and application of both standard and advanced Cypress techniques. From harnessing parallelization via the Cypress Dashboard to judiciously employing cy.wait(), there are many tools at your disposal.

Mocking Over Waiting: Real-world API responses can be time-consuming. By employing mocking techniques like cy.intercept(), you can simulate responses, making your tests swifter and more consistent.

Optimal Resource Use: Advanced techniques, especially running tests in headless mode and managing caches, ensure your testing process is as resource-efficient as possible, translating to faster test cycles.

The Power of Combining Tools: On its own, Cypress is powerful. Yet, when integrated with Launchable, its capabilities are heightened. Launchable's Predictive Test Selection, which runs only the most relevant tests, can transform your development pipeline, ensuring quicker feedback and releases.

Streamlined Testing Pipelines: The combined might of Cypress and Launchable not only speeds up individual test cycles but streamlines your entire testing pipeline. This ensures that the most vital tests, informed by historical data and recent code changes, are always at the forefront, optimizing feedback loops and development processes.

Ready for Change: With the landscape of development and testing constantly evolving, staying equipped with the latest tools and techniques is vital. Launchable transforms complex, voluminous error logs into succinct summaries to quickly identify the crux of issues.

By leveraging Cypress and Launchable, you're future-proofing your testing processes against the demands of tomorrow.