@Test
    void verifyBlockingAction() {
        val properties = new PrincipalTransformationProperties();
        properties.setBlockingPattern(".+@.+\\.com");
        val transformer = PrincipalNameTransformerUtils.newPrincipalNameTransformer(properties);
        assertThrows(PreventedException.class, () -> transformer.transform("hello@cas.com"));
    }
This is {@link PrincipalNameTransformerUtilsTests}.

@author Misagh Moayyed
@since 5.3.0
core/cas-server-core-authentication-api/src/test/java/org/apereo/cas/authentication/principal/PrincipalNameTransformerUtilsTests.java