source: class PropertyTypeTest {
  
      @Test
      public void indentSize() {
  
target:         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());
      }
  
  }