Vanilla JS detection module.

detection.js

// Vanilla JS tests for detecting HTML elements
define('detection', function() {
  if (!document.querySelectorAll) {
    var d=document, s=d.createStyleSheet();
    d.querySelectorAll = function(r, c, i, j, a) {
      a=d.all, c=[], r = r.replace(/\[for\b/gi, '[htmlFor').split(',');
      for (i=r.length; i--;) {
        s.addRule(r[i], 'k:v');
        for (j=a.length; j--;) a[j].currentStyle.k && c.push(a[j]);
        s.removeRule(0);
      }
      return c;
    };
  }

  return {
    // "has()" api: tests for basic CSS selector queries.
    find: function( selector ) {
      return document.querySelectorAll(selector);
    },
    has: function( selector ) {
      return this.find(selector).length > 0;
    }
  };
});