crecker05ru

function createTree({
  data,
  key = 'id',
  parentKey = 'parentId',
  childrenKey = 'children',
}) {
  const tree = Object.fromEntries(data.map(n => [ n[key], { ...n } ]));

  return Object.fromEntries(Object.entries(tree).filter(([ , n ]) => !(
    tree[n[parentKey]] && ((tree[n[parentKey]][childrenKey] ??= {})[n[key]] = n)
  )));
}


const tree = createTree({
  data: arr,
  key: 'uid',
  parentKey: 'parentUID',
});