// Node.prototype.contains (function() { function contains(node) { if (!(0 in arguments)) { throw new TypeError('1 argument is required'); } do { if (this === node) { return true; } // eslint-disable-next-line no-cond-assign } while (node = node && node.parentNode); return false; } // IE if ('HTMLElement' in self && 'contains' in HTMLElement.prototype) { try { delete HTMLElement.prototype.contains; // eslint-disable-next-line no-empty } catch (e) {} } if ('Node' in self) { Node.prototype.contains = contains; } else { document.contains = Element.prototype.contains = contains; } }());