Function stubFetch

apps/host-selfhost/src/telemetry.test.ts:189–193

(respond: (request: Request) => Response)

// setting it discharges no requirement — the layer is `Layer<never>` and works
// by overriding the default in whatever context it is provided to.
const stubFetch = (respond: (request: Request) => Response): Layer.Layer<never> =>
  Layer.succeed(FetchHttpClient.Fetch)(((input: RequestInfo | URL, init?: RequestInit) =>
    Promise.resolve(
      respond(input instanceof Request ? input : new Request(String(input), init)),
    )) as typeof globalThis.fetch);

/**
 * Runs a traced effect against a recording fetch and returns the URLs the