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

Lens

https://github.com/spencer-mortensen/lens

Sleipnir

https://github.com/railsware/Sleipnir
Programming language

PHP

Swift

Category

Unit Testing

Unit Testing, Acceptance Testing

General info

Lens is a unit-testing framework for PHP

Lens is a unit-testing framework for PHP that needs no assertions

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
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

N/A

N/A

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

Yes

It can test front end components

Yes

You can test front-end behaviour by defining specifications for classes, objects and functions
Server-side
Allows testing the bahovior of a server-side code

Yes

It can test back-end behaviour

Yes

You can test back-end behaviour by defining specifications for classes, objects and functions in the back-end
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

N/A

Yes

Fixtures are available by using beforeEach{ } and afterEach{ } to setup the test parameters
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.

N/A

Yes

Group fixtures are available through the beforeAll{} and afterAll{} blocks to setup 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

N/A

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)

N/A

Yes

Yes, developers can create mock objects with sleipnir using a third party library like Cuckoo.
Grouping
Allows organizing tests in groups

N/A

Yes

You can declare example groups with Slepnir
Other
Other useful information about the testing framework