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

NUnit.Framework.Constraints.IConstraint

public interface IConstraint : IResolveConstraint
Interface for all constraints
namespace NUnit.Framework.Constraints { public interface IConstraint : IResolveConstraint { string DisplayName { get; } string Description { get; } object[] Arguments { get; } ConstraintBuilder Builder { get; set; } ConstraintResult ApplyTo<[Nullable(2)] TActual>(TActual actual); ConstraintResult ApplyTo<[Nullable(2)] TActual>(ActualValueDelegate<TActual> del); ConstraintResult ApplyTo<[Nullable(2)] TActual>(ref TActual actual); } }