@Test
    void verifyDefaultImpl() {
        val mock = mock(SamlRegisteredServiceMetadataResolver.class);
        doCallRealMethod().when(mock).saveOrUpdate(any());
        assertThrows(NotImplementedException.class, () -> mock.saveOrUpdate(null));
    }
This is {@link FileSystemResourceMetadataResolverTests}.

@author Misagh Moayyed
@since 6.3.0
support/cas-server-support-saml-idp-metadata/src/test/java/org/apereo/cas/support/saml/services/idp/metadata/cache/resolver/FileSystemResourceMetadataResolverTests.java