@Test
    void verifyBlocked() {
        val pt = new BlockingPrincipalNameTransformer("[abc]");
        assertThrows(PreventedException.class, () -> pt.transform("casuser"));
        assertEquals("helloworld", pt.transform("helloworld"));
    }
This is {@link BlockingPrincipalNameTransformerTests}.

@author Misagh Moayyed
@since 6.4.0
core/cas-server-core-authentication/src/test/java/org/apereo/cas/authentication/handler/BlockingPrincipalNameTransformerTests.java