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

XCTest

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

Espec

https://github.com/antonmi/espec
Programming language

Swift

Elixir

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.

BDD driven testing framework for Elixir

It is a testing framework written from scratch which is inspired by RSpec and the main idea is to close to its perfect DSL (Domain Specific Language)
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

Front-end components can be tested; there is also espec_phoenix for the Phoenix web framework
Server-side
Allows testing the bahovior of a server-side code

Yes

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

Yes

databases and server behaviour can be tested using Espec
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

N/A

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

N/A

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

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

It has a Built-in mocking functionality on top of Erlang 'meck' library
Grouping
Allows organizing tests in groups

Yes

Developers can define test suites from the XCTestSuite class

Yes

By use of context blocksand tags functions
Other
Other useful information about the testing framework