Sleipnir vs WebdriverIO comparison of testing frameworks
What are the differences between Sleipnir and WebdriverIO?

Sleipnir

https://github.com/railsware/Sleipnir

WebdriverIO

https://webdriver.io/
Programming language

Swift

JavaScript

Category

Unit Testing, Acceptance Testing

Browser Automation, Unit Testing, Functional Testing

General info

Sleipnir is a BDD-style framework for Swift

Sleipnir is a pure Swift BDD testing framework inspired by cedar, that is not dependent on NSObject, and does not use XCTest. Sleipnir has nice command line output and support for custom test reporters and other features, like seeded random tests invocation, focused and excluded examples/groups

WebdriverIO is the next-gen WebDriver test framework for Node.js made upon Selenium

WebdriverIO is written in JavaScript and uses Selenium under the hood. It also comes with its own inbuilt test runner and supports other testing frameworks like Jasmine, Cucumber, and Mocha
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

N/A

Yes

Client-side
Allows testing code execution on the client, such as a web browser

Yes

You can test front-end behaviour by defining specifications for classes, objects and functions

Yes

WebdriverIO allows the use of advanced CSS selectors and makes it easy to find elements for front-end testing
Server-side
Allows testing the bahovior of a server-side code

Yes

You can test back-end behaviour by defining specifications for classes, objects and functions in the back-end

Yes

It can be used to test server side behaviour and functionality
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 by using beforeEach{ } and afterEach{ } to setup the test parameters

Yes

WebdriverIO supports the creation of fixtures
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 through the beforeAll{} and afterAll{} blocks to setup group fixtures

Yes

WebdriverIO supports the creation of group fixtures
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

MIT License

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

Yes, developers can create mock objects with sleipnir using a third party library like Cuckoo.

Yes

It contains a mocking service called 'wdio-wiremock-service'
Grouping
Allows organizing tests in groups

Yes

You can declare example groups with Slepnir

Yes

WebdriverIO allows one to build test suites, you can run these test in parallel and organize them by adjusting the 'maxInstances' property in your config file
Other
Other useful information about the testing framework