finally() is not called when returning empty() in catch()

问题

I wrote a generic request method that is supposed to show a loading indicator while the request is running. If an error occurs (like 404), I display the message in .catch and then return Observable.empty(), so that the following code doesn't crash (since no data is returned).

The big problem is that then .finally won't be called either. Is that a bug? Is there a workaround? Here's my code:

res = Observable
  .of(true)
  .do(() => this.store.dispatch(new ShowLoadingIndicatorAction()))
  .switchMap(() => this.http.get(url, { headers: this.headers }))
  .publishReplay(1)
  .refCount()
  .catch(error => {
    this.messages.handleRequestError(error);
    return Observable.empty();
  })
  .finally(() => this.store.dispatch(new HideLoadingIndicatorAction()));

// then later:
res.subscribe(doStuffWithData);

回答1:

What RxJS-version are you using? It does works fine in this example:

const res$ = Rx.Observable
  .of(true)
  .switchMap(() => Rx.Observable.throw("Rest Error"))
  .publishReplay(1)
  .refCount()
  .catch(error => Rx.Observable.empty())
  .finally(() => console.log("Calling Finally!"));

res$.subscribe(console.info);

<script src="https://unpkg.com/rxjs/bundles/Rx.min.js"></script>

来源：https://stackoverflow.com/questions/41999077/finally-is-not-called-when-returning-empty-in-catch