String[] inputs = { "a", "b", "c" };
        CharMappingItem item = new CharMappingItem(1L, inputs, "output");

        assertEquals("a,b,c=>output", item.toLineString());
    }

    public void test_toLineString_withUpdates() {
        String[] inputs = { "old1", "old2" };
        CharMappingItem item = new CharMappingItem(1L, inputs, "oldOutput");

        item.setNewInputs(new String[] { "new1", "new2", "new3" });