title: datetime diff negative result?
body: <p>I have a php code to use calculate different of two DateTime objects, using date_diff procedure. At times the result is negative but it show positive always.</p>
  <p>Code example:</p>
  <pre><code>  $time1 = new DateTime('01:00:00');
    $time2 = new DateTime('02:00:00');
    $resultTime = date_diff($time1, $time2);
    echo &quot;RESULT: &quot;.$resultTime-&gt;format('%h'); // 1
  </code></pre>
  <p>Im expecting -1 here, yet I always get positive 1. Is it possible to show the 'real' result, negative or positive?</p>