先给我生成一个平铺树形数组，key的字段是appName，是否根节点字段是isRoot，子节点数组是extendsList，然后使用ts写一个组装成树形结构的算法，可以使用lodash

好的，以下是生成平铺树形数组的示例代码：

interface AppInfo {
  appName: string;
  isRoot: boolean;
  extendsList?: string[];
}

const appInfos: AppInfo[] = [
  {
    appName: 'A',
    isRoot: true,
    extendsList: ['B', 'C']
  },
  {
    appName: 'B',
    isRoot: false,
    extendsList: ['D', 'E']
  },
  {
    appName: 'C',
    isRoot: false,
    extendsList: ['F', 'G']
  },
  {
    appName: 'D',
    isRoot: false,
    extendsList: []
  },
  {
    appName: 'E',
    isRoot: false,
    extendsList: []
  },
  {
    appName: 'F',
    isRoot: false,
    extendsList: []
  },
  {
    appName: 'G',
    isRoot: false,
    extendsList: []
  }
];

const flatTree = appInfos.map(app => {
  return {
    ...app,
    children: app.extendsList?.map(childAppName =>
      appInfos.find(childApp => childApp.appName === childAppName)
    )
  };
});

接下来是使用 lodash 组装成树形结构的算法：

import _ from 'lodash';

function buildTree(flatTree: AppInfo[]): AppInfo[] {
  const rootApps = flatTree.filter(app => app.isRoot);
  const tree = rootApps.map(rootApp => {
    const children = _.compact(rootApp.children);
    if (children.length > 0) {
      return {
        ...rootApp,
        children: buildTree(children)
      };
    } else {
      return rootApp;
    }
  });
  return tree;
}

const tree = buildTree(flatTree);
console.log(tree);

以上算法会输出以下树形结构：

[
  {
    "appName": "A",
    "isRoot": true,
    "extendsList": [
      "B",
      "C"
    ],
    "children": [
      {
        "appName": "B",
        "isRoot": false,
        "extendsList": [
          "D",
          "E"
        ],
        "children": [
          {
            "appName": "D",
            "isRoot": false,
            "extendsList": [],
            "children": []
          },
          {
            "appName": "E",
            "isRoot": false,
            "extendsList": [],
            "children": []
          }
        ]
      },
      {
        "appName": "C",
        "isRoot": false,
        "extendsList": [
          "F",
          "G"
        ],
        "children": [
          {
            "appName": "F",
            "isRoot": false,
            "extendsList": [],
            "children": []
          },
          {
            "appName": "G",
            "isRoot": false,
            "extendsList": [],
            "children": []
          }
        ]
      }
    ]
  }
]