dom-tools/src/contains.js

A tiny collection of DOM helpers for IE8+.

var canUseDOM = require('./canUseDOM');

// react-bootstrap/dom-helpers 2.4.0 query/contains.js

var contains = (function(){
  var root = canUseDOM && document.documentElement;

  return (root && root.contains)
    ? function(context, node){ return context.contains(node); }
    : (root && root.compareDocumentPosition)
        ? function(context, node){
            return context === node || !!(context.compareDocumentPosition(node) & 16);
          }
        : function(context, node){
            if (node) do {
              if (node === context) return true;
            } while ((node = node.parentNode));

            return false;
          }
})();

module.exports = contains;