@Test
public void indentSize() {

    Assert.assertEquals(PropertyValue.valid("1", 1), PropertyType.indent_size.parse("1"));
    Assert.assertEquals(PropertyValue.valid("tab", null), PropertyType.indent_size.parse("tab"));
    Assert.assertFalse(PropertyType.indent_size.parse("").isValid());
    Assert.assertFalse(PropertyType.indent_size.parse("0").isValid());
    Assert.assertFalse(PropertyType.indent_size.parse("-1").isValid());
    Assert.assertTrue(PropertyType.indent_size.parse("tab").isValid());
    Assert.assertFalse(PropertyType.indent_size.parse(null).isValid());
}