Function stubFetch

packages/react/src/api/tracing.test.ts:9–13

(onRequest: (request: Request) => void)

/** `Fetch` is a Context.Reference defaulting to `globalThis.fetch`, so a stub
 *  layer overrides it without discharging any requirement. */
const stubFetch = (onRequest: (request: Request) => void): Layer.Layer<never> =>
  Layer.succeed(FetchHttpClient.Fetch)(((input: RequestInfo | URL, init?: RequestInit) => {
    onRequest(input instanceof Request ? input : new Request(String(input), init));
    return Promise.resolve(new Response(null, { status: 200 }));
  }) as typeof globalThis.fetch);

// The browser client exports its spans itself — no cloud span processor runs
// in the page — so the scrub is asserted on the serialized OTLP payload the