FetchHandle

type FetchHandle = (
  input: RequestInfo | URL,
  init?: RequestInit,
) => Promise<Response>;

This is the (input, init?) => Promise<Response> call signature Defjs invokes, deliberately not typeof fetch, so a mock does not need host extras such as preconnect. HTTP calls the untouched platform Fetch as (url, init); a replaced global Fetch or custom handle receives a Request. The default resolves the global on each call. SSE always passes a Request, including to its default handle.

Accepted by withHTTPHandle, withSSEHandle, and fetchHandler.