<PackageReference Include="NUnit" Version="4.1.0" />

FalseConstraint

public class FalseConstraint : Constraint
FalseConstraint tests that the actual value is false
using System; using System.Runtime.CompilerServices; namespace NUnit.Framework.Constraints { [System.Runtime.CompilerServices.NullableContext(1)] [System.Runtime.CompilerServices.Nullable(0)] public class FalseConstraint : Constraint { public override string Description => "False"; public override ConstraintResult ApplyTo<[System.Runtime.CompilerServices.Nullable(2)] TActual>(TActual actual) { return new ConstraintResult(this, actual, false.Equals((object)actual)); } public FalseConstraint() : base(Array.Empty<object>()) { } } }