code: function getParentNode(node) {
      return node.__dom && node.__dom.parentNode !== undefined ?
        node.__dom.parentNode : tree.Composed.getParentNode(node);
    }
docs: NOTE: __dom can be created under 2 conditions: (1) an element has a logical tree, or (2) an element is in a logical tree. In case (1), the element will store firstChild/lastChild, and in case (2), the element will store parentNode, nextSibling, previousSibling. This means that the mere existence of __dom is not enough to know if the requested logical data is available and instead we do an explicit undefined check.