[Bug] newHttpBatchRpcSession RequestInit param is silently ignored

[jahands]

The signature in src/index.ts looks like this:

export let newHttpBatchRpcSession:<T extends Serializable<T>>
    (urlOrRequest: string | Request, init?: RequestInit) => RpcStub<T> =
    <any>newHttpBatchRpcSessionImpl;

But the implementation in src/batch.ts takes RpcSessionOptions, not RequestInit:

export function newHttpBatchRpcSession(
    urlOrRequest: string | Request, options?: RpcSessionOptions): RpcStub {
  let sendBatch: SendBatchFunc = async (batch: string[]) => {
    let response = await fetch(urlOrRequest, {
      method: "POST",
      body: batch.join("\n"),
    });

    if (!response.ok) {
      response.body?.cancel();
      throw new Error(`RPC request failed: ${response.status} ${response.statusText}`);
    }

    let body = await response.text();
    return body == "" ? [] : body.split("\n");
  };

  let transport = new BatchClientTransport(sendBatch);
  let rpc = new RpcSession(transport, undefined, options);
  return rpc.getRemoteMain();
}

I found this rather confusing to debug.

[kentonv]

🤦 I had originally designed newHttpBatchRpcSession() to have the same signature as fetch(), but then when I added RpcSessionOptions, I decided that really had to be the second param, and anyway people could always use new Request() to set HTTP request options and still pass that in as the first param. But apparently I forgot to update index.ts or the readme for this and I also totally forgot I made this change altogether, in my head it still had the signature of fetch().