// Test newline replacement in setNewOutput
        item.setNewOutput("line1\nline2\nline3");
        assertEquals("line1 line2 line3", item.getNewOutput());
    }

    @Test
    public void test_setNewOutput_withNull() {
        String[] inputs = { "input" };
        CharMappingItem item = new CharMappingItem(1L, inputs, "output");

        item.setNewOutput(null);
        assertNull(item.getNewOutput());
    }