What is Jest

What is Jest

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Table of Contents
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Lesson Transcript

  • [00:00 - 00:18] In this lesson, we'll learn about just a powerful JavaScript testing framework. Just as a complete JavaScript testing solution, the app as a test runner includes an accession library and isolation framework, and just gives us a built-in test report showing results and coverage.

  • [00:19 - 00:29] So we don't need to add separate libraries to achieve this different concerns. Just has been widely used since its release in 2014.

  • [00:30 - 00:48] According to MPM, just is by far the most popular testing framework for JavaScript, with over 21 million weekly downloads on MPM. Many technology giants have adopted just as their standard testing tool, companies like Facebook, Uber, Paper, and Google.

  • [00:49 - 01:21] Facebook, now known as Meta, open-source, Jest, and it remains one of the most popular repos on GitHub. Some other common choices are Mocha, which is a test runner, and Chai, which is an accession library. Jasmine also provides BDD style writing, but Jest combines the best of all words into a single tool. Also, what the automation is, the NUDS test runner. It provides common features like test runner and isolation framework for mocking, test coverage reporter, and an accession library.

  • [01:22 - 01:49] It is pretty new to the scene. It will take some time to catch up to Jest and be the dominant testing framework. It's worthy to keep an eye on the NUDS test runner, but for now, it's not as matured as Jest. When compared to legacy choices like Mocha and Ch ai, or Jasmine, Jest has seen immense growth in usage, surpassing Mocha as the primary test runner. To give you an idea of skill, Facebook uses Jest to test their massive React codebase.

  • [01:50 - 02:06] With so many industry leaders investing in it, you can feel secure knowing Jest will remain supported for years to come. It's vast community ensures helpful resources are always available. In this course, we will use Jest and also learn best practices. Let's get started with testing.