new String[] { "perm1", "perm2" });

        // Verify the interface extends Serializable
        assertTrue(user instanceof java.io.Serializable);
    }

    @Test
    public void test_allFieldsCombination() {
        // Test with all fields populated
        String name = "complexUser";
        String[] roles = { "admin", "user", "viewer" };
        String[] groups = { "developers", "managers", "qa" };