XCTest vs RSpec comparison of testing frameworks
What are the differences between XCTest and RSpec?

	XCTest https://developer.apple.com/documentation/xctest	RSpec https://rspec.info
Programming language	Swift	Ruby
Category	Unit Testing, Performance Testing	Unit Testing, Intergration 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.	Domain Specific Language (DSL) testing solution for Ruby code It focuses on empowering Test Driven Development (TDD). RSpec contains multiple smaller libraries, which may be independently used with other testing frameworks.
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	Yes Yes, but it differs from more traiditional xUnit solutions. Its tests are written in a "Tests as Specification" manner. This means that the terminology used in RSpec is adjusted to a language more fitting for specification.
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 RSpec is used to primarily test the behaviour of applications or individual components so it can test front-end behaviour as well - you can use capybara gem with RSpec for that.
Server-side Allows testing the bahovior of a server-side code	Yes Yes, developers can test individual back-end components with XCTest	Yes You can test server-side behaviour with Rspec
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 RSpec does contain fixture methods
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 Group fixture methods are supported
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 RSpec contains generators for example intergration_'test_name' which will save a spec inside the spec/requests folder
Licence Licence type governing the use and redistribution of the software	Apache License 2.0	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)	Yes You can create protocol mocks and class mocks with libraries such as MockFive or Cuckoo	Yes Available through rspec-mocks gem.
Grouping Allows organizing tests in groups	Yes Developers can define test suites from the XCTestSuite class	Yes Allows declaring example groups and contexts.
Other Other useful information about the testing framework