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

	Jest https://jestjs.io	Chai https://www.chaijs.com
Programming language	JavaScript	JavaScript
Category	Unit Testing	Unit 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)	Chai is a BDD / TDD assertion library for Node.js and the browser that can be paired with any JavaScript testing framework. Chai is an assertion library, similar to Node's built-in assert and makes testing easier by giving you many assertions you can run against your code. It also includes a robust Plugin architecture for extending Chai's assertions and interfaces.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	No	N/A
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 Chai can be used in a browser environment to test front-end components and functionality
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 Chai is used in a Node.JS environment to test server behaviour and functionality
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.	N/A
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	N/A
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	Yes By using chai-spec-generator plugin which will generate chai test specs from a JavaScript object
Licence Licence type governing the use and redistribution of the software	MIT License	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.	Yes By using by using a third party library like chai-jest-mocks which is a chai plugin that adds assertions for jest mock functions. You can also use sinon.js
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	N/A
Other Other useful information about the testing framework