<PackageReference Include="NUnit" Version="3.9.0" />

TrueConstraint

public class TrueConstraint : Constraint
TrueConstraint tests that the actual value is true
using System; namespace NUnit.Framework.Constraints { public class TrueConstraint : Constraint { public TrueConstraint() : base(Array.Empty<object>()) { Description = "True"; } public override ConstraintResult ApplyTo<TActual>(TActual actual) { return new ConstraintResult(this, actual, true.Equals((object)actual)); } } }