navItem(item) {
    let id = item.getAttribute("id") || undefined;
    let content = Object(core["filterChildren"])(item, "a", true);

    if (!content) {
      return;
    }

    let src = content.getAttribute("href") || "";

    if (!id) {
      id = src;
    }

    let text = content.textContent || "";
    let subitems = [];
    let parentItem = Object(core["getParentByTagName"])(item, "li");
    let parent;

    if (parentItem) {
      parent = parentItem.getAttribute("id");

      if (!parent) {
        const parentContent = Object(core["filterChildren"])(parentItem, "a", true);
        parent = parentContent && parentContent.getAttribute("href");
      }
    }

    while (!parent && parentItem) {
      parentItem = Object(core["getParentByTagName"])(parentItem, "li");

      if (parentItem) {
        parent = parentItem.getAttribute("id");

        if (!parent) {
          const parentContent = Object(core["filterChildren"])(parentItem, "a", true);
          parent = parentContent && parentContent.getAttribute("href");
        }
      }
    }

    return {
      "id": id,
      "href": src,
      "label": text,
      "subitems": subitems,
      "parent": parent
    };
  }
Create a navItem
@private
@param  {element} item
@return {object} navItem