[Bug]: Example given in "Handling return values in forms" section for "use-server" docs fails to compile

use-server ページにあるリンク先の「Handling return values in forms」セクションから始め、そこにある useActionState の例を、リンク先の useActionState ドキュメントと比較します。requestUsername の例を更新して、その引数がドキュメントに記載されたアクションシグネチャと一致するようにし、その後、ドキュメントの例がコンパイルできることを確認します。

Summary

The following example is given in Handling return values in forms section for "use server" docs, fails to compile.

// requestUsername.js
'use server';

export default async function requestUsername(formData) {
  const username = formData.get('username');
  // ..
}

// UsernameForm.js
'use client';

import { useActionState } from 'react';
import requestUsername from './requestUsername';

function UsernameForm() {
  const [state, action] = useActionState(requestUsername, null, 'n/a');
  // ..
}

Page

https://react.dev/reference/rsc/use-server#handling-return-values

Details

It fails to compile because, as per the useActionState docs,

useActionState(action, initialState, permalink?)

the "action" (requestUsername in this case) should have previousState as the first argument,
and formData as the second argument.

However, for the above example, the requestUsername action has formData as the first argument,
rather than previousState. Therefore, it fails to compile.

The following is the correct way mentioned in the useActionState docs:

async function increment(previousState, formData) {
  return previousState + 1;
}

function StatefulForm({}) {
  const [state, formAction] = useActionState(increment, 0);
  // ..
}

I can raise a PR for the fix, if it's okay.