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

	testdouble.js https://github.com/testdouble/testdouble.js	XCTest https://developer.apple.com/documentation/xctest
Programming language	JavaScript	Swift
Category	Unit Testing, Intergration Testing	Unit Testing, Performance Testing
General info	This library was designed to work for both Node.js and browser interpreters and it encourages the TDD (Test Driven Development) Test doubles can be used with conjuction of other test frameworks such as Jasmine, Jest, Chai, QUnit, Mocha, Tape etc.	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.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	Yes It is compatible with xUnit and supportsxUnit XML output	Yes Yes, it is an xUnit style framework
Client-side Allows testing code execution on the client, such as a web browser	No	Yes Developers can test individual front-end components with XCTest
Server-side Allows testing the bahovior of a server-side code	Yes Testdouble is primarily used to test server-side functions, behaviours and components	Yes Yes, developers can test individual back-end components with XCTest
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	N/A	Yes XCTest contains setup() and teardown() fixture methods for setting up and destroying test environments
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.	N/A	Yes Group fixtures are available in XCTest
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	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)	Yes Testdouble includes inbuilt support for mocking	Yes You can create protocol mocks and class mocks with libraries such as MockFive or Cuckoo
Grouping Allows organizing tests in groups	N/A	Yes Developers can define test suites from the XCTestSuite class
Other Other useful information about the testing framework