Kotest vs Buster.JS comparison of testing frameworks
What are the differences between Kotest and Buster.JS?

Kotest

https://github.com/kotest/kotest

Buster.JS

https://busterjs.readthedocs.io
Programming language

Kotlin

JavaScript

Category

Unit Testing

Unit Testing, Browser Automation

General info

kotest is a powerful, elegant and flexible test framework for Kotlin, formerly known as kotlintest

Kotest has excellent support for data driven testing or table driven testing where it has the ability to quickly rerun the same test over and over with a predefined set of inputs and expected values

Buster.JS is a JavaScript test framework for node and browsers.

Buster.JS is a new JavaScript testing framework. It does browser testing by automating test runs in actual browsers (think JsTestDriver), as well as Node.js testing. It has a bunch of great features.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

No

Yes

Buster.Js is a xUnit style Test Framework
Client-side
Allows testing code execution on the client, such as a web browser

Yes

You can test front-end components with kotest

Yes

It does browser testing with browser automation, QUnit style static HTML page testing, testing in headless browsers and more front-end components and functionality
Server-side
Allows testing the bahovior of a server-side code

Yes

Yes, you can test back-end components with kotest

Yes

It is a Node.js testing toolkit as well which means it can test back-end behaviour and functionality as well as run in a server environment
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

kotest contains fixtures, that is the setup / teardown functions

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

kotest has group fixtures available

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

Licence
Licence type governing the use and redistribution of the software

Apache License 2.0

BSD 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)

Yes

You can use a third party library like mockk to create mocks

Buster.JS ships with Sinon.JS. every test in a test case has a sandbox associated with it, making it easy to mock and stub
Grouping
Allows organizing tests in groups

Yes

You can create test suites with kotest

Other
Other useful information about the testing framework