allowedName:                      "abc.com/xyz",
			attributes: &testAttributes{
				resource: certificatesapi.Resource("clustertrustbundles"),
				oldObj: &certificatesapi.ClusterTrustBundle{
					Spec: certificatesapi.ClusterTrustBundleSpec{},
				},
				obj: &certificatesapi.ClusterTrustBundle{
					Spec: certificatesapi.ClusterTrustBundleSpec{},
				},
				operation: admission.Update,
			},
			allowed: true,
		},

				return err
			}
		}
	}
	return nil
}

// CertificateMap is a flat map of certificates, keyed by Name.
type CertificateMap map[string]*KubeadmCert

// CertTree returns a one-level-deep tree, mapping a CA cert to an array of certificates that should be signed by it.
func (m CertificateMap) CertTree() (CertificateTree, error) {
	caMap := make(CertificateTree)

	for _, cert := range m {

		Name:   "leaf1",
		CAName: "root",
	}
	selfSigned := &KubeadmCert{
		Name: "self-signed",
	}

	certMap := CertificateMap{
		"root":        rootCert,
		"leaf0":       leaf0,
		"leaf1":       leaf1,
		"self-signed": selfSigned,
	}

	orphanCertMap := CertificateMap{
		"leaf0": leaf0,
	}

	if _, err := orphanCertMap.CertTree(); err == nil {

	authorizationapiv1 "k8s.io/api/authorization/v1"
	autoscalingapiv1 "k8s.io/api/autoscaling/v1"
	autoscalingapiv2 "k8s.io/api/autoscaling/v2"
	batchapiv1 "k8s.io/api/batch/v1"
	certificatesapiv1 "k8s.io/api/certificates/v1"
	certificatesv1alpha1 "k8s.io/api/certificates/v1alpha1"
	coordinationapiv1 "k8s.io/api/coordination/v1"
	apiv1 "k8s.io/api/core/v1"
	discoveryv1 "k8s.io/api/discovery/v1"