@Test
    void verifyRequestWithInvalidUserCode() throws Throwable {
        val registeredService = getOidcRegisteredService(UUID.randomUUID().toString());
        registeredService.setSupportedGrantTypes(Set.of(OAuth20GrantTypes.CIBA.getType()));
        servicesManager.save(registeredService);
        mvc.perform(post("/cas/" + OidcConstants.BASE_OIDC_URL + '/' + OidcConstants.CIBA_URL)
                .secure(true)
                .header(HttpHeaders.AUTHORIZATION, "Basic " + EncodingUtils.encodeBase64("%s:%s".formatted(registeredService.getClientId(),
                    registeredService.getClientSecret()).getBytes(StandardCharsets.UTF_8)))
                .queryParam(OAuth20Constants.SCOPE, OidcConstants.StandardScopes.OPENID.getScope())
                .queryParam(OAuth20Constants.GRANT_TYPE, OAuth20GrantTypes.CIBA.name())
                .queryParam(OidcConstants.USER_CODE, UUID.randomUUID().toString())
                .queryParam(OidcConstants.LOGIN_HINT, UUID.randomUUID().toString())
            )
            .andExpect(status().isBadRequest());

        registeredService.setBackchannelUserCodeParameterSupported(true);
        servicesManager.save(registeredService);
        mvc.perform(post("/cas/" + OidcConstants.BASE_OIDC_URL + '/' + OidcConstants.CIBA_URL)
                .secure(true)
                .header(HttpHeaders.AUTHORIZATION, "Basic " + EncodingUtils.encodeBase64("%s:%s".formatted(registeredService.getClientId(),
                    registeredService.getClientSecret()).getBytes(StandardCharsets.UTF_8)))
                .queryParam(OAuth20Constants.SCOPE, OidcConstants.StandardScopes.OPENID.getScope())
                .queryParam(OAuth20Constants.GRANT_TYPE, OAuth20GrantTypes.CIBA.name())
                .queryParam(OidcConstants.LOGIN_HINT, UUID.randomUUID().toString())
            )
            .andExpect(status().isBadRequest());
    }
This is {@link OidcCibaControllerTests}.

@author Misagh Moayyed
@since 7.1.0
support/cas-server-support-oidc/src/test/java/org/apereo/cas/oidc/web/controllers/ciba/OidcCibaControllerTests.java