Minimizing the running time for various operations is crucial in the modern world. The same is true when running tests. Executing tests in parallel is one of the most common strategies to run more test cases in less time. It may take a long time for tests to finish running in serial on a single machine if the project includes many tests. When executing tests in Continuous Integration, your team can save time and money by running them in parallel across numerous virtual machines (CI). Since version 3.1.0, Cypress has supported the concurrent execution of recorded tests over numerous computers.
While it is possible to conduct parallel tests on a single machine, still it is not advisable doing so because it would be difficult to execute the tests effectively. This guide is all about Cypress parallel testing.
Before diving into Parallel Test Execution with Cypress, let’s get a general overview of parallel testing.
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Parallel Testing
To continue providing high-quality applications in the lowest amount of time parallel testing is the preferred method for increased test efficiency and quicker turnaround in application delivery. Instead of running one test at a time in order, parallel testing enables the execution of many tests simultaneously.
The term “parallel testing” is frequently used in the context of automated testing, which enables developers and testers to run several tests concurrently against various real device and browser configurations. Parallel testing aims to overcome time restrictions by dividing tests among available resources.
On the other hand, sequential testing is the opposite of parallel testing, often known as serial testing. This traditional testing method causes a backlog of test work and extends the time it takes to market.
Due to the current market’s rising demand for cross-browser testing, parallel test execution has become more popular. It enables testers to run test cases concurrently across many browsers. The testers will thereby save a lot of time and effort.
Advantages of Parallel Testing
Faster Execution- Tests are run simultaneously on several instances of computers, which speeds up test results retrieval and reduces execution time. Parallel testing is superior to sequential testing because it can protect your team from delivery delays without sacrificing quality.
Less Work- Tests are done on a variety of browser-device-operating system combinations, thus eliminating the need for testers to manually wait for one test to finish before starting another on a different browser.
Better test coverage- Parallel testing enables the testing on multiple devices, browsers, and operating system combinations and helps to attain maximum test coverage without lengthening execution time or sacrificing the reliability of the outcomes.
Cost-Efficient- It can be expensive to create, manage and keep your test environment. Maintenance is no longer a hassle when it comes to parallel testing. You hire the required testing environment, which is constantly updated.
Optimization of Your CI/CD Processes- Continuous integration and delivery benefit greatly from parallel testing. Conducting parallel testing you may run tests as soon as developers submit new code updates.
Improvement of Testing Practices- Parallel testing enhances your company’s QA practice. This is simply because you can test more by running tests quickly.
Challenges of Parallel Testing
The main difficulty in parallel testing is building up the necessary infrastructure to carry out the tests. Running several browser instances simultaneously on one computer can eventually overburden it and result in incorrect failure results.
It would be easier for teams with access to a device lab to access various combinations of actual browsers, devices (particularly mobile), and operating systems (consistently maintained and updated).
Therefore, this solution is using a cloud-based testing platform like LambdaTest. This platform makes it much simpler for QAs to run concurrent tests. Testers get access to a cloud of more than 3000 actual browsers, devices, and operating systems combinations. It gives teams the ability to run Selenium, Appium, or Cypress tests simultaneously online on the desired real device-browser combinations. Testers can validate the functionality of websites under actual user situations without the restrictions of emulators and simulators.
What is Cypress?
Cypress is an end-to-end testing framework built on JavaScript, constructed on top of the Javascript-based test framework Mocha. It is an open-source automation tool that is free. It seeks to address the challenges that QA engineers or developers encounter when testing an application.
Cypress is a more developer-friendly tool that functions directly in the browser and makes use of a novel DOM manipulation technique. Additionally, Cypress offers an interactive test script runner with visual stimuli for running test cases. This aids the tester in understanding how the program being tested behaves during each test phase.
What is Cypress parallel test execution?
For interface testing of web applications, the Cypress.io platform is ideal. Its primary responsibility is to examine how the client component communicates with the server component and how the various page elements communicate with one another.
By running the test cases on CI Tools, Cypress makes it easy to run multiple tests at once. The tester can also run the test cases simultaneously on the local device. It is not suggested, though, as it will slow the CPU and eat up more resources. It is always good to run it while setting up parallel execution on the CI tools.
How to Parallelize Cypress Tests
Cypress’s Parallel Execution is especially helpful because it speeds up the continuous testing process. It helps to execute several test cases in a short amount of time.
By setting up numerous machines, Cypress offers a Parallel Testing option. To get going, one must set up a parallel testing approach according to the requirements of a certain project. This procedure may be difficult and lengthy depending on the task and the team. Maintaining the test infrastructure is a significant task unless one uses a test-ready environment for parallel testing in Cypress like LambdaTest.
Cypress may also integrate with CircleCI, GitLab, and other platforms, to create continuous testing and parallelization.
Why Parallel Testing with Cypress?
Cypress can be used in place of or in combination with other web testing frameworks for a variety of reasons while doing web tests. Here are some of the main characteristics and advantages:
Time Travelling
As your tests are running, Cypress takes snapshots. In the Command Log, users can click over commands to observe what went at each stage.
Screenshots and Videos
When the test suite is run via the CLI, you may view videos of the full test suite as well as screenshots that are automatically taken upon failure.
Network Traffic Control
Simple stub control and edge case testing without involving your server. Network traffic can be stubbed in any way you desire.
Debuggability
Developer Tools directly allow users to debug. It provides legible errors and stack traces that accelerate debugging.
Consistent Results
WebDriver is not used in Cypress architecture. Because of this, it is quick, reliable, and produces results that are free of flake.
Automatic Waiting
Testing with Cypress never involves waiting or sleeping. It waits for commands and assertions automatically before continuing.
Spies, Stubs, and Clocks
Cypress checks and regulates how timers, servers, or functions behave.
Active Community
The Cypress framework is open-source and free. It has a freemium business strategy, allowing you to choose between the free and premium versions. The advanced capabilities of the premium edition include video storage and a dashboard with artifacts like DOM snapshots that are useful for troubleshooting. Cypress has a thriving community on GitHub, Gitter, and StackOverflow, and interest in it is on the rise.
Running Cypress Tests parallelly on LambdaTest
Users must set up the entire infrastructure and direct Cypress to run their tests because Cypress only allows parallel testing in multiple virtual machine instances. However, since they have already created the infrastructure, the ideal strategy is to leverage cloud-based platform testing solutions. The cloud already has real browsers and devices; all you need to do is write test scripts and run the tests.
Users may execute Cypress tests on the newest browsers using LambdaTest. Without needing to keep up with countless Docker images, you may also run a large number of Cypress tests simultaneously. Starting to run Cypress tests on LambdaTest is simple which only requires a few simple steps.
Utilize Cypress’s many benefits to conduct parallel tests with ease. Even when running several tests concurrently, use LambdaTest’s real browsers to ensure that all tests deliver 100% accurate results. If you want to build web applications that are customer-ready and thoroughly optimized, don’t limit your testing to the numerous shortcomings of emulators and simulators. Only use the real thing.
Steps to execute Cypress Tests in Parallel on LambdaTest
You have a choice between the following two methods for running your tests in parallel on the LambdaTest platform;
Perform the Cypress tests using the CLI in parallel
You must run your tests with the “parallels” option if you want to execute Cypress testing in parallel using the CLI.
Carry out the Cypress tests using Lambdatest-configuration in parallel .file in json
The Lambda test configuration can also be used to run Cypress tests concurrently using the ‘parallels’ key in a json file.
Conclusion
Cypress’s use of parallel execution is highly advantageous because it speeds up the continuous testing process. It helps execute a lot of test cases in a short amount of time. Parallel testing is superior to sequential testing because it can protect your team from delivery delays without sacrificing quality.
Parallelization lowers QA costs by providing high case concurrency, streamlining CI/CD workflows, and continuously enhancing scripts to deliver more precise results. However, without a good strategy, all these benefits are inaccessible. You can fully profit from parallel testing if you test in a cloud-based environment, prevent hard coding, remove data dependencies, and script with parallelization in mind.