selected node get xpath

getXPath.js

function getXPath(nodeElem) {
  const parts = [];
  while (nodeElem && nodeElem.nodeType === Node.ELEMENT_NODE) {
    let nbOfPreviousSiblings = 0;
    let hasNextSiblings = false;
    let sibling = nodeElem.previousSibling;
    while (sibling) {
      if (
        sibling.nodeType !== Node.DOCUMENT_TYPE_NODE &&
        sibling.nodeName === nodeElem.nodeName
      ) {
        nbOfPreviousSiblings++;
      }
      sibling = sibling.previousSibling;
    }
    sibling = nodeElem.nextSibling;
    while (sibling) {
      if (sibling.nodeName === nodeElem.nodeName) {
        hasNextSiblings = true;
        break;
      }
      sibling = sibling.nextSibling;
    }
    const prefix = nodeElem.prefix ? nodeElem.prefix + ":" : "";
    const nth =
      nbOfPreviousSiblings || hasNextSiblings
        ? `[${nbOfPreviousSiblings + 1}]`
        : "";
    parts.push(prefix + nodeElem.localName + nth);
    nodeElem = nodeElem.parentNode;
  }
  return parts.length ? "/" + parts.reverse().join("/") : "";
}