sizzle :invalid selector

HTML

<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
<form>
  <input type="text" id="valid" value="foo" required>
  <input type="text" id="invalid" required>
  <button type="button" id="validate">validate</button>
</form>

JavaScript

$('#validate').on('click', function () {
  var findInvalidInputs = $('form').find('input:invalid');
  console.log('findInvalidInputs', findInvalidInputs);
  var findInputsFilterInvalid = $('form').find('input').filter('input:invalid');
  console.log('findInputsFilterInvalid', findInputsFilterInvalid);
});