AVA vs xUnit.net comparison of testing frameworks
What are the differences between AVA and xUnit.net?

AVA

https://github.com/avajs/ava

xUnit.net

https://xunit.net/
Programming language

JavaScript

.NET

Category

Unit Testing, Intergration Testing

Unit Testing

General info

Futuristic, new, fast and concurrent JavaScript test runner with simple test syntax

AVA is a test runner for Node.js with a concise API, detailed error output. JS is a single-threaded but Node.JS is a parallel due to it's async behaviour. Ava leverages that and it can run tests concurrently

xUnit.net is aUnit testing framework for C# and .NET

xUnit.net is a free, open source, community-focused unit testing tool for the .NET Framework. It is used to test C#, F#, VB.NET and other .NET languages. xUnit.net and works with ReSharper, CodeRush, TestDriven.NET and Xamarin. It is part of the .NET Foundation,
xUnit
Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.

No

However Ava supports the TAP format which allows us to use the tap-xunit reporter to produce xUnit (JUnit) XML

Yes

xUnit.net is part of the xUnit family of frameworks
Client-side
Allows testing code execution on the client, such as a web browser

Yes

You can write tests for the DOM with Ava, testing front-end components is easy with Ava

Yes

You can test various front-end components independently since it is a Unit testing framework
Server-side
Allows testing the bahovior of a server-side code

Yes

Ava utilizes the async I/O nature of Node and runs concurrent tests on NodeJs applications' back-endsA node server can have its endpoints tested with Ava

Yes

You can test various back-end components independently since it is a Unit testing framework
Fixtures
Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test

Yes

Using Ava's ava-fixture library it supports fixtures

Yes

It contains class fixtures which are setup once pertest class
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

Ava has support for group fixtures

Yes

xUnit.net contains collection fixtures which allow you to share context among many 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

Licence
Licence type governing the use and redistribution of the software

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)

AVA has no mocking built in, to mock functions you can use third party libraries like Sinon.js.

Grouping
Allows organizing tests in groups

No

There is no support for grouping tests

Other
Other useful information about the testing framework