// When newInput is set back to null
        item.setNewInput(null);
        assertEquals("original", item.toLineString());
    }

    public void test_toLineString_withEmptyInput() {
        // Test toLineString with empty original input
        StopwordsItem item = new StopwordsItem(1, "");
        assertEquals("", item.toLineString());

        item.setNewInput("new");

        // Test with item created with id=0
        ProtwordsItem newItem = new ProtwordsItem(0, "newword");
        assertEquals("newword", newItem.toLineString());
    }

    public void test_toLineString_withEmptyInput() {
        // Test toLineString with empty input
        ProtwordsItem item = new ProtwordsItem(1, "");
        assertEquals("", item.toLineString());

        item.setNewInput("word");