xUnit VS Fluent Assertions

Compare xUnit vs Fluent Assertions and see what are their differences.

xUnit

xUnit.net is a free, open source, community-focused unit testing tool for .NET. (by xunit)

Fluent Assertions

A very extensive set of extension methods that allow you to more naturally specify the expected outcome of a TDD or BDD-style unit tests. Targets .NET Framework 4.7, as well as .NET Core 2.1, .NET Core 3.0, .NET 6, .NET Standard 2.0 and 2.1. Supports the unit test frameworks MSTest2, NUnit3, XUnit2, MSpec, and NSpec3. (by fluentassertions)
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xUnit Fluent Assertions
36 7
3,991 3,558
1.3% 1.3%
9.2 9.6
3 days ago 8 days ago
C# C#
GNU General Public License v3.0 or later Apache License 2.0
The number of mentions indicates the total number of mentions that we've tracked plus the number of user suggested alternatives.
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.

xUnit

Posts with mentions or reviews of xUnit. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2023-11-14.
  • Optimizing C# code analysis for quicker .NET compilation
    4 projects | dev.to | 14 Nov 2023
    Several well-known NuGet packages such as xUnit.net, FluentAssertions, StyleCop, Entity Framework Core, and others include by default a significant number of Roslyn analyzers. They help you adhere to the conventions and best practices of these libraries.
  • Comprehensive Unit Testing: A Line-by-Line Approach
    2 projects | dev.to | 12 Sep 2023
    xUnit -> https://xunit.net/
  • CI/CD Pipeline Using GitHub Actions: Automate Software Delivery
    8 projects | dev.to | 21 Jul 2023
    .NET / xUnit / NUnit / MSTest
  • Fluent Assertions: Fluently Assert the Result of .NET Tests
    3 projects | dev.to | 11 Jul 2023
    This library extends the traditional assertions provided by frameworks like MSTest, NUnit, or XUnit by offering a more extensive set of extension methods. Fluent Assertions supports a wide range of types like collections, strings, and objects and even allows for more advanced assertions like throwing exceptions.
  • Running a XUnit test with C#?
    3 projects | /r/csharp | 28 May 2023
    The git repo has other runners. AssemblyRunner appears to be the best fit for an already compiled tests project, but there is a runner that can be wrapped into an MSBuild task for example.
  • Setting up a simple testing project with C#
    7 projects | dev.to | 27 May 2023
    At this point you're going to see a familiar screen asking you to select a project. Here we're looking for a test project. By default, Visual Studio gives you access to 3 different testing frameworks based on your choice of project. These are MSTest, XUnit and NUnit. Ultimately, all 3 of these testing accomplish the same thing, and I've worked with all of them at various points in my career. The difference is mainly in exact syntax and documentation. Although, it's generally considered that MSTest is a little "older" than NUnit or XUnit, so I tend to see it less now. For the purposes of this demo, I'm going to go with NUnit:
  • Integration tests for AWS serverless solution
    4 projects | dev.to | 15 May 2023
    xUnit unit tests tool
  • Test-Driven Development
    3 projects | dev.to | 4 May 2023
    Use a testing framework: Utilize a testing framework like NUnit, xUnit, or MSTest to create, organize, and run your tests. These frameworks provide a consistent way to write tests, generate test reports, and integrate with continuous integration tools.
  • NUnit vs XUnit for .net6+ microservices
    7 projects | /r/dotnet | 1 Mar 2023
    Attachments: At this time you still cannot attach files to test runs, although the functionality finally is coming in V3!
  • Creating Your Own Custom Attributes in C# and Retrieving Their Values
    3 projects | dev.to | 17 Dec 2022
    I was trying to think of an example of where C# attributes might be used in every day life and then it dawned on me: unit testing! If you have ever used a unit test framework such as MSTest, NUnit or xUnit, you will have used attributes in C# to define the classes and methods that you would like the test framework to execute. This is just one example of how you can use attributes to assign metadata to elements of your code.

Fluent Assertions

Posts with mentions or reviews of Fluent Assertions. We have used some of these posts to build our list of alternatives and similar projects. The last one was on 2022-12-20.
  • Integration tests without API dependencies with ASP.NET Core and WireMock.Net
    5 projects | dev.to | 20 Dec 2022
  • [Parte 8] ASP.NET Core: Integration Tests
    4 projects | dev.to | 13 Apr 2022
    FluentAssertions para Asserts muy flexibles y entendibles
  • BREAKING!! NPM package ‘ua-parser-js’ with more than 7M weekly download is compromised
    32 projects | /r/programming | 22 Oct 2021
    https://www.nuget.org/packages/Newtonsoft.Json/ https://www.nuget.org/packages/AutoMapper/ https://www.nuget.org/packages/Dapper/ https://www.nuget.org/packages/FluentValidation/ https://www.nuget.org/packages/FluentAssertions/ https://www.nuget.org/packages/NUnit/ https://www.nuget.org/packages/xunit/ https://www.nuget.org/packages/YamlDotNet/ https://www.nuget.org/packages/Moq/ That is simply not true. Mature c# projects purposely maintain no downstream dependencies and is they do, it's to a major reputable lib. See for yourself - these are staple third party packages commonly used. Anything dependency starting with System or NETStandard is Microsoft maintained.
  • ASP.NET Core Unit Testing with FluentAssertions
    3 projects | dev.to | 21 Aug 2021
    FluentAssertions is one of the most popular (over 66 million downloads on Nuget) .NET library that contains a large collection of .NET extension methods that allow .NET developers to write unit tests using a fluent syntax which is very easy to read and write and clearly shows the intent of the unit test. The library has extension methods to test almost everything related to .NET such as Strings, Booleans, Dates, Guids, Collections, Exceptions, and even Nullable Types. You can add this library to your unit test projects via Nuget package manager and start using this library in few minutes.
  • My first NuGet package: Fluent Random Picker
    4 projects | /r/csharp | 27 Jun 2021
    I love fluency. I myself work on a package for fluent programming. I recommend you using FluentAssertions for tests though. Nonetheless, keep working! Starred your repo.
  • Honk#! Honk in convenient C# now!
    5 projects | /r/csharp | 23 Jun 2021
    For example, all tests below this line are written in Honk# + FluentAssertions (the latter is an example of a library which also provides a lot of fluent methods for xUnit to perform assertions). Soon I'll be moving more of its (AngouriMath's) code to this style, as long as it doesn't harm readability and performance.
  • Cell CMS - Criando testes de maneira prática
    6 projects | dev.to | 31 Jan 2021
    fluentassertions / fluentassertions

What are some alternatives?

When comparing xUnit and Fluent Assertions you can also consider the following projects:

Shouldly - Should testing for .NET—the way assertions should be!

NUnit - NUnit Framework

NFluent - Smooth your .NET TDD experience with NFluent! NFluent is an ergonomic assertion library which aims to fluent your .NET TDD experience (based on simple Check.That() assertion statements). NFluent aims your tests to be fluent to write (with a super-duper-happy 'dot' auto-completion experience), fluent to read (i.e. as close as possible to plain English expression), but also fluent to troubleshoot, in a less-error-prone way comparing to the classical .NET test frameworks. NFluent is also directly inspired by the awesome Java FEST Fluent assertion/reflection library (http://fest.easytesting.org/)

SpecFlow - #1 .NET BDD Framework. SpecFlow automates your testing & works with your existing code. Find Bugs before they happen. Behavior Driven Development helps developers, testers, and business representatives to get a better understanding of their collaboration

Moq - Repo for managing Moq 4.x [Moved to: https://github.com/moq/moq]

NSubstitute - A friendly substitute for .NET mocking libraries.

MSTest - MSTest framework and adapter

AutoFixture - AutoFixture is an open source library for .NET designed to minimize the 'Arrange' phase of your unit tests in order to maximize maintainability. Its primary goal is to allow developers to focus on what is being tested rather than how to setup the test scenario, by making it easier to create object graphs containing test data.