title: jQuery data attribute selector issue
body: <p>I am trying to show some span`s with data attribute base on select options available.</p>
  
  <p>I am using the below code</p>
  
  <pre><code>  $("#pa_varsta option").each(function(i){
          var marime =  $(this).val();
          $('.tawcvs-swatches [data-value=' + marime + ']').show();
      });
  </code></pre>
  
  <p>But i get the error</p>
  
  <pre><code>jquery.js?ver=1.12.4:2 Uncaught Error: Syntax error, unrecognized expression: .tawcvs-swatches [data-value=]
  </code></pre>
  
  <p>I am using Wordpress.</p>
  
  <p>Any ideea, maybe regarding the jquery version?</p>