We are using numerous blessings of technology every moment but, as normal users, we hardly pay attention to the huge operations going on behind those web products and services. With every passing moment, the requirement for more advanced & efficient features is getting higher, user databases are becoming huge, and eventually, the demand from technology is touching the sky. Developers are constantly brainstorming on efficient web products and developing new features along with ensuring the best performance from those products. But, as we all know, maintaining them is more important than keeping on developing more applications. QA is the most effective way to achieve the best quality and efficiency.
If we talk about QA, we can never undervalue Cypress tests, the most widely used, efficient way to ensure the best quality of your web products. While the cypress tests can be really helpful, the flaky ones can cause massive setbacks in performance and waste a lot of time & resources. That’s why we are going to know about the flaky cypress tests in detail and explore the ways to deal with them.
If you observe some tests failing at random intervals while no one is making any changes to the code, then those tests can be called flaky. These tests make you confused whether the tests are flaky or you are observing bugs, and to detect that, you get to rerun the same tests multiple times. As a result, your CI/CD pipeline gets significantly slowed down and eventually the flaky tests lead you towards unpredictability & frustration due to repeated troubleshooting. In the long-term, these can make your customers lose trust in your product and your business will face immense downfall. Hence, we must work out some useful and efficient ways to deal with them.
There are mainly two ways to detect if any cypress test is flaky or not. One is rerunning a test or even a whole test suite multiple times without any change in the code to see if there is any change in the number of failed test suites at every run. If the number is different every time or most of the time, then there is something wrong with your test suite.
In the second method, you need to rerun the test in a different order each time. If your test fails due to a change in the order, you may have forgotten to take interdependencies into account.
Now, as we make you familiar with the hardships in detecting flaky Cypress tests or executing the Cypress tests in general, we must provide you with a way to get rid of those issues. So, Preflight’s Cypress recorder lets you create your tests in minutes, and that too using a user-friendly interface. After you are done creating your test, you will get its auto-generated Cypress code instantly. Then you are free to run those codes with all the customizations that you want. Our tool lets you conduct numerous tests with the most efficient cypress code generated in minutes. Anyone with no coding knowledge can also easily generate Cypress test codes and execute massive QA projects within the shortest amount of time.
After detecting the Flaky cypress tests, it’s time to get rid of them so that your product doesn’t lose its place in the market. Let’s check out the best practices for that.
In order to get rid of flaky cypress tests, you must visualize them first. Visualizing multiple randomized test runs will let you analyze how well your tests are performing and let you observe the increment or decrement in the number of flaky tests. Developing a table with well-organized rows and columns helps you achieve the best results in visualizing test runs.
One crucial cause of flaky tests is repeated interaction with elements in the DOM that do not render consistently. Those elements may look fine when they are tested manually but they produce errors during Cypress tests. Cypress keeps on retrying the commands without maintaining the best-suited order on the malfunctioning elements. The best way to solve the issue is combining the commands like .get(), .find() in single commands and setting assertions for those single commands. It mainly retries the command that is prior to the assertion that failed in the chain. Another reason for this kind of flakiness is the timing of the events that mostly deal with various input fields. You can use custom Cypress commands to resolve this problem. So, from this point, we can conclude that one of the best ways to get rid of the flaky Cypress tests is by asserting every command that you want Cypress to retry and using custom Cypress commands wherever necessary.
Flaky tests need to be rerun multiple times with implemented solutions to check whether they are getting resolved or not. But, operating on them when they are among the non-flaky tests causes the rerunning of the entire test suite and eventually, the efficiency reduces. Hence, the best way of resolving this is to create a separate test suite for them. A separate test suite prevents duplication in the part of work required to solve the flaky tests. It provides you the opportunity to fix the flaky tests without any interruption. This way you will get a better idea about the role of inter-test dependence in flakiness.
Another form of flakiness is caused by inconsistent responses to network requests. Such flakiness can occur when the test execution continues even without a request having received a response. But, the good news is that there is an efficient solution to this issue. You can use intercept commands to stub responses for the requests that you want to receive a successful response. This is a nice strategy for testing a page that makes calls to external APIs. Besides using intercept commands, using Cypress fixtures is another great way to ensure that the flakiness is reduced.
If the test execution continues without a network request getting properly finished, it can cause flakiness. And, if you manually enforce waiting time, it can increase the overall time required for the test suite to run. Hence, an effective method to get rid of this issue is using parallelization in the CI pipeline.
Previously generated data that you have forgotten about can cause the present tests to get off the expected track. These states and data can stay in the caches, databases, or even variables. Stay aware of the cleaning-up state after the test is completed. Often clean-up errors are ignored. The worst-case scenario is rebuilding the whole system for every test run. As transactions can be rolled back after a test run, the database can be brought back to its old state.
Asynchronous tests are a form of test that needs significant access to network resources. We all know that the network turns out to be fast or slow depending on the services using it. As a result, the asynchronous tests often become flaky due to timeouts. And, the more crucial thing is that too short timeouts can cause significant flakiness in tests. The best practices to prevent this type of flakiness are -
Some services do not focus on minutely determining if the test is the real one or somewhat duplicate. So, you can easily create a simplified version of the actual test. Though there are debates on the fact that test doubles are not always equivalent to the real ones, they are truly useful to look for updates without experiencing flakiness with the real services.
The system clock is a type of data that cannot be known in advance. And, there are several tests that depend on this data. Using faulty data can cause immense flakiness in the Cypress tests. Hence, the best practice for getting rid of it is wrapping such data sources in your code and avoiding direct reliance on them. That way you can replace their outputs with hard-coded data before running a test.
Available resources and other systems running on any hardware are extremely crucial for testing it. If your code that uses those resources has memory leaks, it becomes the cause of flakiness in the tests. You can decide if your code has memory leaks by observing if the memory usage of the test suite grows with every test run.
This flakiness can be controlled if the failure of the tests is pre-known. And, that can be achieved by using resource allocation pools as wrappers between your code and the actual memory allocation. Then the flakiness can be fixed by controlling the memory allocation.
Preflight always makes sure that our clients get the best service and the most convenient user experience from our products. Similarly, to deal with flaky Cypress tests, you can access the following awesome features on our dashboard.
The better choice between these is the CSS selectors as they are easier to read and front-end developers can easily deal with them. While you are building your selectors manually, our smart features help you add markups in your application that are used exclusively by the selectors in your tests. Adding these attributes will give your automation an explicit, and hopefully static, element identifier.
We went through some of the most useful and effective ways to deal with flaky Cypress tests. You can stay assured that Team Preflight is continuously digging and brainstorming to find out the most efficient features to provide the best automated testing experience to our users. You can just check out how our simple yet smartest browser extension lets you create and perform numerous complex tests in minutes. We also have the most efficient Cypress Test Recorder that enables you to create complex tests in a glimpse and generates their Cypress codes within moments.