assertTrue(tags.contains("existing"));
    }

    @Test
    public void testConcatValues() {
        // Test static concatValues method
        List<String> dest = new java.util.ArrayList<>();
        dest.add("existing");

        SuggestItem.concatValues(dest, "new1", "new2", "existing");

        assertEquals(3, dest.size());
        assertTrue(dest.contains("existing"));