@Test
    void verifyResolverWithBadSigningCert() throws Throwable {
        val service = new SamlRegisteredService();
        service.setMetadataMaxValidity(30000);
        service.setMetadataCriteriaRoles(String.join(",", Set.of(
            IDPSSODescriptor.DEFAULT_ELEMENT_NAME.getLocalPart(),
            SPSSODescriptor.DEFAULT_ELEMENT_NAME.getLocalPart())));
        service.setMetadataLocation(METADATA_FILE.getCanonicalPath());
        service.setMetadataSignatureLocation("classpath:inc-md-cert.pem");
        assertTrue(metadataResolver.resolve(service).isEmpty());
    }
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