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

	Spek https://www.spekframework.org/	XCTest https://developer.apple.com/documentation/xctest
Programming language	Kotlin	Swift
Category	Acceptance Testing, Unit Testing	Unit Testing, Performance Testing
General info	Spek is a specification framework for Kotlin Spek is a Kotlin-based Specification Testing framework for the JVM. It works as a JUnit 5 Test Engine meaning that we can easily plug it into any project that already uses JUnit 5 to run alongside any other tests that we might have.	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.	No	Yes Yes, it is an xUnit style framework
Client-side Allows testing code execution on the client, such as a web browser	Yes Yes you can test front-end behaviour by writing specifications to test front-end functionality. Developers can also write unit tests for individual front-end components.	Yes Developers can test individual front-end components with XCTest
Server-side Allows testing the bahovior of a server-side code	Yes You can test back-end behaviour and componets by writing specifications to test back-end functionality and unit tests for individual back-end 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	Yes Fixtures are available in spek through functions suchas beforeEachTest() and afterEachTest()	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.	Yes spek has group fixtures available through the beforeGroup() and afterGroup() functions	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	N/A
Licence Licence type governing the use and redistribution of the software	Modified BSD 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 You can use the third party library mockito-kotlin	Yes You can create protocol mocks and class mocks with libraries such as MockFive or Cuckoo
Grouping Allows organizing tests in groups	Yes Tests are written using nested lambdas, each scope (level) can either be a group or a test	Yes Developers can define test suites from the XCTestSuite class
Other Other useful information about the testing framework