@Test
  public void getCredentialsShouldReturnNullIfEmptyPeerAuthInit() throws Exception {
    props.setProperty(SECURITY_PEER_AUTH_INIT, "");
    Properties credentials = authenticator.getCredentials(member, props);
    assertThat(credentials).isNull();
  }
Unit tests GMSAuthenticator using old security.
geode-core/src/test/java/org/apache/geode/distributed/internal/membership/adapter/auth/GMSAuthenticatorWithAuthenticatorTest.java