FluentAssertions

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 4.5 and 4.7, as well as .NET Core 2.0, .NET Core 3.0, .NET Core 2.1, .NET Standard 1.3, 1.6, 2.0 and 2.1. Supports the unit test frameworks MSTest, MSTest2, Gallio, NUnit, XUnit, MBUnit, MSpec, and NSpec.