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

	XCTest https://developer.apple.com/documentation/xctest	Spock http://spockframework.org/
Programming language	Swift	Java
Category	Unit Testing, Performance Testing	Unit 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.	Spock is a testing and specification framework for Java and Groovy applications Spock has a highly expressive specification language, and due to its JUnit runner, Spock is compatible with most IDEs, build tools, and continuous integration servers.Spock is inspired from JUnit, RSpec, jMock, Mockito, Groovy, Scala, Vulcans among others
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	No
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 Spock tests front-end components and functionality by unit testing individual classes and functions
Server-side Allows testing the bahovior of a server-side code	Yes Yes, developers can test individual back-end components with XCTest	Yes Spock tests back-end components and functionality by unit testing individual classes and functions
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 Spock contains four methods for setting up environments :setup() (run before every feature method), cleanup() (run after every feature method), setupSpec() (run before the first feature method), cleanupSpec() (run after the last feature method)
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 You can use the fixture methods to setup environments for groups of tests.
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	Apache License 2.0	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 create protocol mocks and class mocks with libraries such as MockFive or Cuckoo	Yes Spock has inbuilt mocking capabilities and has no need for external libraries
Grouping Allows organizing tests in groups	Yes Developers can define test suites from the XCTestSuite class	Yes You can create suites manually in spock
Other Other useful information about the testing framework