assertNotNull(result);
        assertSame(messages, result);
        assertTrue(messages.hasMessageOf(property));
    }

    // Test null property handling
    @Test
    public void test_addErrorsFrontHeader_nullProperty() {
        try {
            messages.addErrorsFrontHeader(null);
            fail("Should throw exception for null property");
        } catch (IllegalArgumentException e) {
            // Expected