GitHub repository: Djohnnie/fluentassertions
Primary language: C#
Description: Fluent API for asserting the results of unit tests that targets .NET Framework 4.5, 4.7, .NET Standard 1.3, 1.6 and 2.0. Supports the unit test frameworks MSTest, MSTest2, Gallio, NUnit, XUnit, MBunit, MSpec, and NSpec.