export default can not be typed via jsdoc

[daKmoR]

Bug Report

🔎 Search Terms

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about jsdoc and export default

⏯ Playground Link

/**
 * The complete Triforce, or one or more components of the Triforce.
 * 
 * @typedef {Object} WishGranter
 * @property {boolean} hasCourage - Indicates whether the Courage component is present.
 * @property {boolean} hasPower - Indicates whether the Power component is present.
 * @property {boolean} hasWisdom - Indicates whether the Wisdom component is present.
 */

/** @type {WishGranter} */
const works = {
  hasCourage: true,
  foo: false // correctly errors
}

// does not work for export default

/** @type {WishGranter} */
export default {
  hasCourage: true,
  foo: false // no error
}

// workaround that "breaks" prettier e.g. you can't format anymore as it will remove the `()`
// https://github.com/prettier/prettier/issues/11279

///** @type {WishGranter} */
//export default ({
//  // type RocketCliConfig
//});

Compiler Options

{
  "compilerOptions": {
    "strict": true,
    "noImplicitAny": true,
    "strictFunctionTypes": true,
    "strictPropertyInitialization": true,
    "strictBindCallApply": true,
    "noImplicitThis": true,
    "noImplicitReturns": true,
    "alwaysStrict": true,
    "esModuleInterop": true,
    "checkJs": true,
    "allowJs": true,
    "declaration": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "target": "ES2017",
    "jsx": "react",
    "module": "ESNext",
    "moduleResolution": "node"
  }
}

Playground Link: Provided

💻 Code

/** @type {import('rocket/cli').RocketCliConfig} */
export default {
  // "no" type - e.g. any
} 

🙁 Actual behavior

It does not put any type for export default.

🙂 Expected behavior

/** @type {import('rocket/cli').RocketCliConfig} */
export default {
  // type RocketCliConfig
} 

😅 Workaround

A possible workaround is to typecast via () but that "breaks" prettier as it will always remove it as "usless" brackets.
See prettier/prettier#11279

/** @type {import('rocket/cli').RocketCliConfig} */
export default ({
  // type RocketCliConfig
})

[daKmoR]

ah sorry the correct syntax is

export default /** @type {import('rocket/cli').RocketCliConfig} */ ({
  // type RocketCliConfig
})

which works fine with prettier

[daKmoR]

actually, it would be nice if you could export default an object directly....

[a-tarasyuk]

In the following example, JSDoc definition works like type assertion

export default /** @type */ ({ })

TS

interface Foo {
  a: number;
}
export default ({ b: 1 }) as Foo;

Do we need to have the same behavior for the next case?

/** @type {Foo} */ 
export default { b: 1 } // apply type assertion

/cc @RyanCavanaugh @sandersn

[sandersn]

this syntax makes sense to me. one investigation item: what does the jsdoc tool do here? I don't think their docs cover ES imports so it's down to the implementation.

However, even if jsdoc doesn't support this, I think it's a good idea.

[a-tarasyuk]

@sandersn Thanks for the answer. I think it behaves like so

/** @type {Foo} */
export default { b: 1, a: 2 }

import foo from "./c";
foo // type Foo

If acceptable to add type assertion, I can try to make POC