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

Jest

https://jestjs.io

TestNG

https://testng.org/doc/documentation-main.html
Programming language

JavaScript

Java

Category

Unit Testing

Unit Testing, Intergration Testing, End-to-End 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)

TestNG is a testing framework for the Java programming language inspired by JUnit and NUnit

TestNG is similar to JUnit and NUnit but with newer functionalities such as: annotations, test that your code is multithread safe, flexible test configuration, support for data-driven testing (with @DataProvider), support for parameters, powerful execution model (no more TestSuite) and more... It's also designed to cover all categories of tests unit, functional, end-to-end, intergration... etc
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

No

No

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

The scope of testing with testNg is wide and you can test various front-end functionalities and behaviours with it
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 server-side functionalities and behaviours with TestNg
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

Fixtures are inbuilt into testNG, these are the annotations which are: @BeforeSuite, @AfterSuite, @BeforeTest, @AfterTest, @BeforeGroups, @AfterGroups, @BeforeClass, @AfterClass, @BeforeMethod, @AfterMethod
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 various fixtures to setup environments for group tests
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

N/A

Licence
Licence type governing the use and redistribution of the software

MIT License

Apache License 2.0

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 Use of an external library like mockit which intergrates well with testNG
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

Multiple test cases can be grouped more easily by converting them into testng.xml file, in which you can make priorities which test case should be executed first
Other
Other useful information about the testing framework