The dom.iterable lib contains many interfaces that should also be in webworker

Many of the interfaces defined in dom.iterable should also be available to web workers. These include:

• Headers
• FormData
• URLSearchParams

And since the dom.iterable library does not play well with the webworker library, I have to define these interfaces in my own, separate, library (instead of just including built-in libraries).

The webworker library should either also have an “iterable” variant, or these interfaces should be abstracted to a higher level.

TypeScript Version: 3.5.3, master

Search Terms: dom iterable worker

Code

// index.ts
const h = new Headers();

console.log([...h.entries()]);

const h = new Headers();

console.log([...h.entries()]);
tsc --target esnext --lib esnext,webworker index.ts

Expected behavior:

This should compile fine (as it does when using --lib esnext,dom,dom.iterable).

Actual behavior:

index.ts:3:19 - error TS2339: Property 'entries' does not exist on type 'Headers'.

3 console.log([...h.entries()]);
                    ~~~~~~~

Found 1 error.

Playground Link:

Can’t show this in the playground as I can’t specify --lib options.

Related Issues:

Somewhat related to: https://github.com/microsoft/TypeScript/issues/20595

[sandersn]

Unfortunately, I missed this for 3.8. I’m going to move to 3.9 and look at it early in the release cycle with @orta.

[tankakatan]

The problem is still present in TypeScript 4.3.4 and it’s really annoying. I use jest@27.0.5 in conjunction with ts-jest@27.0.3 in my project, and it fails to compile my tests because of the issue. Please resolve.