`isUnexpected` should handle the streaming responses

[deyaaeldeen]

isUnexpected is generated with overloads where each one corresponds to a REST API call. However, it doesn't take into account situations when the customer calls .asNodeStream or .asBrowserStream. We expect overloads for HttpNodeStreamResponse and HttpBrowserStreamResponse to be supported.

Here is my proposal:

export interface DefaultResponse extends HttpResponse {
  status: string;
  body: ErrorResponse;
  headers: RawHttpHeaders & DefaultHeaders;
}

export function isUnexpected(
  response: HttpBrowserStreamResponse | HttpNodeStreamResponse | DefaultResponse
): response is DefaultResponse;

[MaryGao]

Thanks for the proposal! The current implementation didn't consider the streaming situations becuase every operation could return HttpNodeStreamResponse and HttpBrowserStreamResponse. So the type systems may fail to suggest the unexpected response if different operations have different default response shapes. The type system would always return the first one matched.

export function isUnexpected(
  response:
    | StringGetNotProvided200Response
    | StringGetNotProvidedDefaultResponse
    | HttpBrowserStreamResponse // Adding stream response
    | HttpNodeStreamResponse
): response is StringGetNotProvidedDefaultResponse;
export function isUnexpected(
  response:
    | StringGetBase64Encoded200Response
    | StringGetBase64EncodedDefaultResponse
    | HttpBrowserStreamResponse // Adding stream response
    | HttpNodeStreamResponse
): response is StringGetBase64EncodedDefaultResponse;

I may re-think if we have a better way to solve this and feel free to share your ideas!