<PackageReference Include="NUnit" Version="4.3.2" />

NUnit.Framework.Constraints.PropOperator

Operator used to test for the presence of a named Property on an object and optionally apply further tests to the value of that property.
namespace NUnit.Framework.Constraints { public class PropOperator : SelfResolvingOperator { public string Name { get; } public PropOperator(string name); } }