<PackageReference Include="NUnit" Version="4.2.1" />

TestAssemblyDirectoryResolveAttribute

Marks a test assembly as needing a special assembly resolution hook that will explicitly search the test assembly's directory for dependent assemblies. This works around a conflict between mixed-mode assembly initialization and tests running in their own AppDomain in some cases.
using System; namespace NUnit.Framework { [AttributeUsage(AttributeTargets.Assembly, AllowMultiple = false, Inherited = false)] public class TestAssemblyDirectoryResolveAttribute : NUnitAttribute { } }