In lib.d.ts hasn't signature for formData types (Fetch API)

[alfaslash]

TypeScript Version: 2.2.1

After adding typings for Fetch API in core typescript I got an error Property 'formData' does not exist on type 'Response'. Because in lib.dom.d.ts I see:

interface Body {
    readonly bodyUsed: boolean;
    arrayBuffer(): Promise<ArrayBuffer>;
    blob(): Promise<Blob>;
    json(): Promise<any>;
    text(): Promise<string>;
}

But for typings whatwg-fetch:

interface Body {
    readonly bodyUsed: boolean;
    arrayBuffer(): Promise<ArrayBuffer>;
    blob(): Promise<Blob>;
    formData(): Promise<FormData>;
    json(): Promise<any>;
    json<T>(): Promise<T>;
    text(): Promise<string>;
}

And this types in Fetch API spec https://fetch.spec.whatwg.org/#body

I sent a PR to the repository TSJS-lib-generator

[mhegazy]

PRs welcomed. You can find more information about contributing lib.d.ts fixes at https://github.com/Microsoft/TypeScript/blob/master/CONTRIBUTING.md#contributing-libdts-fixes.

[alfaslash]

My PR was merged.

[mhegazy]

We still need to port the changes from https://github.com/Microsoft/TSJS-lib-generator. keeping it open until a new drop is ported.