* [Signature.getInstance]. Typical values are like "SHA256WithRSA".
   */
  val signatureAlgorithmName: String
    get() {
      return when (signature.algorithm) {
        ObjectIdentifiers.SHA256_WITH_RSA_ENCRYPTION -> "SHA256WithRSA"
        ObjectIdentifiers.SHA256_WITH_ECDSA -> "SHA256withECDSA"

        .certificateAuthority(0)
        .ecdsa256()
        .signedBy(root)
        .build()
    assertThat(root.certificate.sigAlgName).isEqualTo("SHA256WITHRSA", ignoreCase = true)
    assertThat(leaf.certificate.sigAlgName).isEqualTo("SHA256WITHRSA", ignoreCase = true)
  }

  @Test
  fun rsaSignedByEcdsa() {
    val root =
      HeldCertificate.Builder()
        .certificateAuthority(0)