public void CertificateDoesNotExist(IEnumerable <Task> tasks) { InstallParam p = new InstallParam("somename", "somevalue"); tasks.First().LocalParams.Add(p); CertificateValidator val = Substitute.ForPartsOf <CertificateValidator>(); val.WhenForAnyArgs(a => a.FindCertificates(null)).DoNotCallBase(); val.FindCertificates(null).ReturnsForAnyArgs(new X509Certificate2Collection()); val.Data["StoreName"] = "Root"; val.Data["ParamNames"] = p.Name; Assert.DoesNotContain(val.Evaluate(tasks), r => r.State == Sitecore9Installer.Validation.ValidatorState.Error); val.DidNotReceiveWithAnyArgs().ValidateCertificate(null); }