assertEquals(List.of("#", "# List of good fruits", "#"), o21);
        Object o2 = p1.getProperty("fruits");
        assertEquals("apple, banana, pear", o2);
    }

    @Test
    public void testSubstitution() throws IOException {
        String str = "port = 4141" + LINE_SEPARATOR + "host = localhost"
                + LINE_SEPARATOR + "url = https://${host}:${port}/service"
                + LINE_SEPARATOR;