Arquillian vs NaturalSpec comparison of testing frameworks
What are the differences between Arquillian and NaturalSpec?

Arquillian

http://arquillian.org/

NaturalSpec

https://www.nuget.org/packages/NaturalSpec/
Programming language

Java

.NET

Category

Intergration Testing, Functional Testing

Unit Testing

General info

Arquillian is an Open source framework for writing Integration and functional tests

Arquilian comes bundled with many extra tools such as Arquillian graphene, Drone and Selenium to write tests to the visual layer as well

NaturalSpec is a .NET Unit testing framework

NaturalSpec is a .NET UnitTest framework which provides automatically testable specs in natural language. NaturalSpec is based on NUnit and completely written in F# - you don't have to learn F# to use it.
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

Yes

It is a xUnit framework

No

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

Yes

You can perform unit tests on front-end components and functionality

Yes

You can test front-end components with NaturalSpecit. It is a Unit testing framework therefore you can test front-end modules and classes independently
Server-side
Allows testing the bahovior of a server-side code

Yes

You can unit tests on back-end behaviours and functionalities by testing specific back-end classes and functions

Yes

You can test back-end components with NaturalSpec. It is a Unit testing framework therefore you can test back-end modules and classes independently
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

By use of extensions, for example you can use the Persistence extension to set database fixtures

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

You can define group fixtures

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

Arquillian supports mock object functionality you can use third party libraries

Yes

Mocks are available through third party libraries like Moq
Grouping
Allows organizing tests in groups

Yes

Arquilian supports grouping of tests

N/A

Other
Other useful information about the testing framework