Jest is a framework for testing applications written in Javascript which used to perform unit tests, including those whose purpose is to validate a small part of the application. An example of this is whether a given variable takes a specific value. Unit tests are very important if we want our application to develop smoothly and be scalable, because later changes within a given fragment of the code may affect the test result, so it protects us in the event of incorrect changes that may occur in the code in the future. For testing applications written in PHP, you can use, for example, PHPUnit, and the Laravel framework has its own built-in test tools.tools.

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