XCTest vs Unit.js comparison of testing frameworks
What are the differences between XCTest and Unit.js?

XCTest

https://developer.apple.com/documentation/xctest

Unit.js

https://unitjs.com/
Programming language

Swift

JavaScript

Category

Unit Testing, Performance Testing

Unit Testing, End-to-End Testing

General info

XCTest is the default testing framework for unit tests, performance tests, and some level of UI tests for iOS apps.

XCTest framework is a testing framework that enables developers write basic unit tests, performance tests, and some level of UI tests for iOS apps.

An assertion library for JavaScript (similar to chai.js)

It works with any test runner and unit testing framework like Mocha, Jasmine, Karma, protractor (E2E test framework for Angular apps) and QUnit.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

Yes

Yes, it is an xUnit style framework

Client-side
Allows testing code execution on the client, such as a web browser

Yes

Developers can test individual front-end components with XCTest

Yes

Unit.js runs in the browser to test front-end components
Server-side
Allows testing the bahovior of a server-side code

Yes

Yes, developers can test individual back-end components with XCTest

Yes

Unit.js runs in nodejs to test server-side behaviour
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

XCTest contains setup() and teardown() fixture methods for setting up and destroying test environments

Yes

Unit.js provides Test fixtures for running testsThis is one of its features
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

Group fixtures are available in XCTest

Yes

With Unit.js you can group your 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

Licence
Licence type governing the use and redistribution of the software

Apache License 2.0

GNU

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 create protocol mocks and class mocks with libraries such as MockFive or Cuckoo

N/A

Grouping
Allows organizing tests in groups

Yes

Developers can define test suites from the XCTestSuite class

N/A

Other
Other useful information about the testing framework