组树形菜单

let arr = [
  { id: 1, parent: null, text: '菜单1' },
  { id: 11, parent: 1, text: '菜单1-1' },
  { id: 111, parent: 11, text: '菜单1-1-1' },

  { id: 1111, parent: 111, text: '菜单1-1-1-1' },
  { id: 1112, parent: 111, text: '菜单1-1-1-2' },

  { id: 112, parent: 11, text: '菜单1-1-2' },
  { id: 12, parent: 1, text: '菜单1-2' },
  { id: 2, parent: null, text: '菜单2' },
  { id: 21, parent: 2, text: '菜单2-1' },
  { id: 22, parent: 2, text: '菜单2-2' },
];
function getTreeList1(rootList, id, list) {
  for (let item of rootList) {
    if (item.parent == id) {
      list.push(item);
    }
  }
  for (let i of list) {
    i.children = [];
    getTreeList(rootList, i.id, i.children);
    if(i.children.length==0 ){
        delete i.children
    }
  }
  return list;
}

let res = getTreeList(arr, null, []);

console.log(res)