<PackageReference Include="NUnit" Version="3.0.0" />

IFixtureBuilder

public interface IFixtureBuilder
The IFixtureBuilder interface is exposed by a class that knows how to build a TestFixture from one or more Types. In general, it is exposed by an attribute, but may be implemented in a helper class used by the attribute in some cases.
using NUnit.Framework.Internal; using System.Collections.Generic; namespace NUnit.Framework.Interfaces { public interface IFixtureBuilder { IEnumerable<TestSuite> BuildFrom(ITypeInfo typeInfo); } }