return null;
            }
        };
        FessUserBean user = FessUserBean.empty();
        assertNull(ssoManager.logout(user));
    }

    public void test_logout_withValidAuthenticator() {
        currentSsoType = "test";
        final String expectedLogoutUrl = "https://example.com/logout";
        testAuthenticator.setLogoutUrl(expectedLogoutUrl);