Jest vs JUnit comparison of testing frameworks
What are the differences between Jest and JUnit?

	Jest https://jestjs.io	JUnit https://junit.org/junit5/
Programming language	JavaScript	Java
Category	Unit Testing	Unit Testing, Regression Testing
General info	A Unit Testing framework focused on simplicity This is a Unit test framwork especially designed for the React.JS, Babel, TypeScript, Node, React, Angular and Vue projects. It usually worked with Enzyme(Integration testing)	JUnit is an open source Unit testing framework for java JUnit is useful for developers to write and run repeatable tests. JUnit has been crucial in the development of test driven development and is partof the xUnit family of unit testing frameworks
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	No	Yes It is an instance of the xUnit architecture for unit testing frameworks.
Client-side Allows testing code execution on the client, such as a web browser	Yes You can easily test methods, properties, UI element actions and other front-end functionalities	Yes You can test front-end components such as individual classes and functions that create the front-end
Server-side Allows testing the bahovior of a server-side code	Yes Back-end server behaviour also can be tested with Jest much in the same way as the front-end tests.	Yes You can test classes and functions that compose the back-end such as database connections and so on
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	Yes Fixtures are supported, Jest has many helper functions such as: BeforeEach and afterEach If you have some work you need to do repeatedly for many tests, beforeAll and afterAll if you only need to do setup once, at the beginning of a file.	Yes JUnit contains a setUp() method, which runs before every test invocation and a tearDown() method, which runs after every test method.
Group fixtures Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.	Yes Jest supports group fixtures	Yes You can use setUp() and tearDown() inbuilt functions as group fixtures.
Generators Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.	N/A	You can use JUnit-quickcheck to generate test data
Licence Licence type governing the use and redistribution of the software	MIT License
Mocks Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)	Jest uses a custom resolver for imports in your tests making it simple to mock any object outside of your test’s scope. You can use mocked imports with the rich Mock Functions API to spy on function calls with readable test syntax.	JUnit does not support mocking internally but you can use a mock framework like Mockito to generate mock objects.
Grouping Allows organizing tests in groups	Yes You can declare as many test suites as you want. Grouping of tests together is done using a describe block	Yes In JUnit you can create a test suite that bundles a few unit test cases and runs them together. You use both @RunWith and @Suite annotation are used to run the suite test.
Other Other useful information about the testing framework