With the widespread adoption of agile methodologies, teams are now required to release more frequently and within shorter time frames. This requires not only shorter development cycles but also higher quality applications. With this approach, there is no immediate need for manual testing once the path is set for automation testing. But with an increased pace of change, companies are requiring greater automation testing coverage along with sticking to traditional regression testing techniques.
By utilizing a comprehensive approach to automation testing, we can ensure that the software product is robust and meets the desired threshold of quality. Given the wide range of programming languages and test automation frameworks available in the market, it is important to identify the right set of languages and corresponding frameworks for the success of your test automation strategy.
Why do we need Unit Testing?
A unit is the smallest piece of code that can be logically isolated in the system. Unit testing means testing these independent or individual units. Unit testing is often associated as a part of the programming phase, i.e., developer-based testing. But why should developers write tests? Let’s understand the benefits.
Early detection of bugs in the development phase itself, i.e., even before the QA phase. This, in turn, makes the testing phase easier
When a developer further develops the code base, unit tests help ensure that the new code doesn’t break the existing old features. This will boost the developer’s confidence in maintaining the code quality
Easy to make code changes aided by the instant feedback loop
Saves time and money in the long run
Now let us examine the pros and cons of Jest.
The key benefit of using Jest is that it is very easy to install with zero setup hiccups. In addition, Jest provides you with an integrated framework that is ready to use, aiming for an out-of-the-box experience.
It is maintained and well documented, making it easy to learn, especially for developers new to the TDD (Test Driven Development) approach.
Jest is a fast-performing test automation framework where isolated tests are executed by performing parallel testing in their processes.
Jest provides testing support for asynchronous code.
Jest framework supports execution of Smart Visual Regression Tests by capturing screenshots (i.e. Snapshot testing). During development using ReactJS, this particular feature comes in handy for detecting UI bugs. This is done by recording the screenshot of a rendered component and then comparing it with the component rendered in the future test run. Also, when a new feature is added, the screenshots can be easily updated.
Auto mocking is another out-of-the-box feature of Jest. Jest can easily mock any dependency imported in the module that needs to be tested in the future.
Jest library provides pre-commit hooks that allow running only relevant tests or running tests that have changed after the last commit.
The code mods module offers many ways to integrate your current projects to sync with the latest framework seamlessly.
Other than the ones listed above, here are some more liked aspects of Jest, making it a likeable product for developers.
Who uses Jest?
Prominent companies that reportedly adopt Jest in their tech stack are:
Facebook, Airbnb, Spotify, The New York Times, Travel Perk, Twitter, Instagram, etc.
Cons of Jest
Jest has proven to be a powerful tool to do almost anything. However, while Jest has several advantages, it also has a few disadvantages. For example, it is an expensive framework, and at times its debugging capabilities need improvement. Below are a few cons of Jest:
Compared to Jasmine and other frameworks, not many libraries and toolings are supported by Jest.
People who are not comfortable with the Jest framework have asserted that the learning curve is pretty hard.
Leveraging auto mocking can make tests slow. This is because the more dependencies a module has, the more work needs to be done by Jest to mock it, which comes at the cost of performance.
Snapshot testing with Jest is not so feasible for larger snapshot files containing thousands of lines.
Other than the ones listed above, here are some of the disliked aspects of Jest among developers who picked “used it and would not use it again.”
Note: ES6 Generators have a number of applications but mostly they can be used to control the iteration behavior of a loop.
It is quite easy to install the Mocha framework. All you require is a workstation and you can install Mocha using the NPM commands.
Let us examine the pros and cons of Mocha.
Mocha offers a programmatic way to write code for performing Selenium automation testing. It categorizes the tests into suites and test cases for execution, producing error reports after the run by mapping errors to corresponding test cases.
So, if you’re curious about the world of Mocha, this video will help you get started. You’ll learn how to write and run your first test case in Mocha and much more.
However, you can follow the LambdaTest YouTube Channel by scanning the below QR code and stay up to date with more such videos.
Clear and simple API. The Mocha API can be considered similar to Jasmine but coated with a bit of syntactic sugar to make it more conducive to a wider range of scenarios like BDD.
Mocha is highly extensible and flexible. Unlike Jest, Mocha doesn’t come with the mocking, assertion, or stubbing library. This means that the developer can select any library or framework. One popular choice is Chai and Sinon for mocking. Cypress, the popular test automation framework, also leverages the Chai library. You can find more details about it in the Cypress Architecture blog that deep dives into the architectural aspects of the framework.
In Mocha, tests are run serially. This allows flexible and accurate reporting while mapping uncaught exceptions to the correct test cases.
Mocha is a library of functions for testing your code in different online browsers. It is easy to use and makes running code on multiple browsers a breeze while giving you all the flexibility you need to test on each browser separately or in groups.
The reporting tool includes various report types, namely — list, progress bar, output file, JSON. The default reporter displays results hierarchically based on the structure of test cases.
Mocha supports both Behavior Driven Development (BDD) and Test Driven Development (TDD), allowing writing high-quality tests.
Since Mocha is mature with widespread adoption, lots of tutorials and documents are available online. In addition to being open-source, Mocha is backed by active support from the Mocha Dev community.
It can easily support generators.
Support for both synchronous and asynchronous testing.
Supports Headless running out of the box.
Many CI servers support Mocha.
Other than the ones listed above, here are some more liked aspects of Mocha among developers who picked “used it and would use again.”
Who uses Mocha?
Prominent companies that reportedly adopt Mocha in their tech stack are:
Accenture, Coursera, Netifly, Oyo rooms, Codefirst, Asana, Wix, Yahoo, etc.
Cons of Mocha
Although Mocha has proven to be a powerful tool in most cases, some areas still need improvement. The following list mentions some of the major cons of using Mocha:
The introduction of Jest has significantly diminished the popularity of Mocha.
Unlike Jest, which works as a single and independent framework, Mocha requires more configuration, making it weaker.
Even though it can boast of having a vast ecosystem, it is complicated as well.
In Mocha, auto-mocking and snapshot testing are not easy.
Developer tooling and more onboard features can help Mocha perform better.
Other than the ones listed above, here are some of the disliked aspects of Mocha among developers who picked “used it and would not use it again.”
Installation of Jasmine is very simple. All you require is a workstation with internet connectivity and you can install Jasmine using the NPM commands.
However, compared to Jest, the configuration of Jasmine is a bit complex. Before running test cases, the test.js file needs to be set up and configured.
Let us examine the pros and cons of Jasmine.
Jasmine provides a rich set of built-in matchers that can match expectations and add asserts to the test cases. For example, we can use toEqual, toBe, toBeTruthy, toBeFalsy, and more.
The Jasmine BDD library makes it easy to define tests, run them, and integrate them with JSHint, all without tying tests to a specific test runner.
It offers clean and polished syntax.
Supports headless running out of the box.
Various CI servers support the Jasmine framework.
Since it has been in the market for a long time, Jasmine is supported by an active community, and lots of tutorial materials are available online. This can make your learning curve smooth.
As of writing this blog, there are close to 13,000 questions that are tagged Jasmine on Stack Overflow.
Other than the ones listed above, here are some more liked aspects of Jasmine among developers who picked “used it and would use again.”
Who uses Jasmine?
Prominent companies that reportedly adopt Jasmine in their tech stack are:
Accenture, Walmart, Typeform, GitLab, Uniqlo, etc.
Cons of Jasmine
Although Jasmine is powerful, they are not without their weaknesses. The following list mentions some of the major cons of Jasmine:
Though the installation is easy, the setup is a bit complex. Users must select an assertion or mocking library before using it.
Supports snapshot testing by using the jasmine-snapshot library. However, the integration isn’t that easy.
Asynchronous testing is difficult to achieve with Jasmine.
Expect a specific suffix to all test files (*.spec.js by default).
Other than the ones listed above, here are some of the disliked aspects of Jasmine among developers who picked “used it and would not use it again.”
Jest vs Mocha vs Jasmine — Choosing the right framework
We have evaluated the pros and cons of the three frameworks. But still, confused about which is the ideal framework for you?
When it comes to selecting between frameworks, honestly, it is not that easy. We cannot claim that one framework is better than the other as each of these frameworks offers a unique set of features with a different approach in coding style. So finally, it all comes down to your project requirements.
In this section of the Jest vs Mocha vs Jasmine comparison, we will shortlist some of the general criteria widely embraced by project teams to choose the right test automation framework.
For React or Next.js apps, it is advisable to try out Jest as it is the default option. At present, Facebook has been investing heavily in further improving this framework. Also, React developers are recording a positive experience after using Jest.
If the project requires debugging the test cases in an IDE that Jest does not support, then the next best choice would be Jasmine.
If your project is quite big and requires the integration of various external libraries, Jasmine would be a better choice. On the other hand, Jest would be more suitable for smaller projects as it provides a single integrated eco-space with pre-configured features like the test runner, assertion library, etc.
When it comes to large Node.js projects, Mocha could be the way to go. Mocha is significantly more flexible and comes with a test runner, but you have to piece it yourself.
In the Angular world, Jasmine is the recommended testing framework. This is because Angular CLI, by default, comes with Jasmine and Karma as the test runner. However, if there is a future requirement, migrating from Jasmine to Jest is easy.
It is clear that currently, the popularity of Jest as a faster-performing framework with the least configuration requirement has surely made a significant impact in the automation testing domain.
As the development of web applications is becoming more dynamic, developers are expected to roll out an upgraded version of the application in shorter release cycles. As the testing needs to go hand in hand with the development velocity, it is natural for developers to go after tools that can make their job quicker, reliable, efficient, and at the same time, cost-effective.
LambaTest now integrates with popular test automation frameworks to boost your go-to-market delivery. The good news is that whatever your test framework — Jest, Mocha, Jasmine, Protractor, Karma, etc. — LambdaTest got it all covered! Here’s a list of LambdaTest integrations. The platform provides you the infrastructure to execute your automation tests and ensure your development code renders seamlessly through an on-cloud Selenium Grid. Additionally, through parallel testing, you can drastically trim down your testing cycles.
Sounds too good to be true, right? And all these benefits can be unlocked through a few simple configuration changes in your test automation framework. So do check out the LambdaTest platform to fast-track your automation testing today!
Note: Lookbehind in JS regular expressions, the positive lookbehind (
(?<= )) and negative lookbehind (
(?<! )) zero-width assertions can be used to confirm that one pattern is followed by another.
Jest vs Mocha vs Jasmine: The Final Showdown
Top comments (1)
Very useful post, thank you! I'm currently studying Mocha, but I'm also very interested in Cypress. What do you think about it?