为什么 vscode 不能自动完成导出的对象，从一个文件到另一个文件，在 nodejs 中？ 它是性能特征吗？

Question

Problem

In my usecase, i maintain my database config/connections using sequelize in a separate file models/index.js . I export the database connection object(called db ) so that other modules can connect to the database. But when I require the object in some other file, no auto-completions are shown for that object nor its corresponding properties.

Context

This is how my part of my models/index.js file looks like, which i have done like the official sequelize example :-

const { Sequelize } = require('sequelize');
const sequelize = new Sequelize(config);
let db = {};
// for each of the files `file` in a dir...dynamically do(refer above linked example for details):-
let model = require(path.join(__dirname, file))(sequelize, Sequelize);
db[model.name] = model; // type Sequelize.Model
// dynamic config over

// statically add
db.sequelize = sequelize; // type Sequelize
module.exports = db

This is how i have imported in another module:-

const db = require("./models/index.js");
db.seq -------------------------------> where i try for auto-completion

Expectation

When i require my database connection object db in another file, it should provide auto-completion for the properties i statically assigned, like db.sequelize should be a completion and further db.sequelize.xxx , where xxx is the corresponding sequelize methods and properties should also be auto-completed.

What's the behavior now?

Typing db. doesn't show any valid auto-completions pertaining to the object db . Also db.sequelize has a type any for the sequelize part(so no further auto-completions), whereas I expected it to be Sequelize .

What I have done?

• Explicitly added jsdoc , thinking that's the only way to make the auto-completions work, but to no use:-

/**
* @typedef {import('sequelize').Sequelize} Sequelize
*/

const { Sequelize } = require('sequelize');
/**
 * @type {Sequelize}
 */
const sequelize = new Sequelize(config);
/**
 * key : string -> Name of the Sequelize.Model | 'sequelize'
 * value : Either one of the Models or Sequelize object
 * @type {Object.<string,(Sequelize|Sequelize.Model)>}
 * @property {Sequelize} sequelize
 * @example
 * db = { User: db.User , seqeuelize : sequelize}
 */
let db = {};
// rest of the dynamic processing and adding Sequelize.Model to db
db.sequelize = sequelize;
module.exports = db

• Added a jsconfig.json with following content, but that was also futile:-

{
  // NOTE THAT, this file resides within my src/server/ directory where all the js files exists
  // the models/index.js resides within src/server
  // I maintain another jsconfig for src/client
  "compilerOptions": {
    "module": "commonjs",
    "target": "es6",
    "allowSyntheticDefaultImports": true,
    "moduleResolution": "node",
    "experimentalDecorators":true,
    "baseUrl": ".",
    "paths": {
      "*": ["*"],
    },
  },
  "include": ["./**/*"],
}

Answer 1

If you change your object let db = {}; to let db = {sequelize: null}; , you will get intellisense to work as intended.