node.js `fetch` is wrongly typed

[bpasero]

⚙ Compilation target

ESNext

⚙ Library

5.8

Missing / Incorrect Definition

https://undici.nodejs.org/#/docs/api/Dispatcher?id=parameter-responsedata

But thats not the case.

Sample Code

async function foo() {
    const res = await fetch('https://example.com');
    console.log(await res.bytes()); // error: Property 'bytes' does not exist on type 'Response'.ts(2339)
}

foo();

Documentation Link

No response

[jakebailey]

Do you have the DOM types loaded? If you do, they will take precedence over Node's.

[jakebailey]

(but, this is not really a problem with TypeScript)

[bpasero]

No, I do not, this is a 1-file project with:

{
  "compilerOptions": {
    "target": "ESNext",
    "module": "ESNext",
    "lib": ["ESNext"],
    "types": [
        "node"
    ],
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true
  },
  "include": ["index.ts"],
  "exclude": ["node_modules"]
}

{
    "name": "name",
    "description": "description",
    "authors": "author",
    "version": "1.0.0",
    "main": "pathToMain",
    "devDependencies": {
        "@types/node": "22.x"
    }
}

[jakebailey]

Okay, then this is an issue with undici, whose types the node types import. TypeScript just loads them, we have no control over their contents.

[bpasero]

Understood, do you happen to know where to report?

[jakebailey]

https://github.com/nodejs/undici is where undici-types is published from.

[bpasero]

Thanks, will report it there!

[bpasero]

nodejs/undici#4271