🐞 bug report

Affected Package

Is this a regression?

Description

Previously, unhandled errors from promises were handed to a custom error handler unchanged. But now, it seems the error is wrapped and you need to unwrap it to get the real error that's sitting on the "rejection" property of the error.

The docs make no mention of this here https://angular.io/api/core/ErrorHandler and neither does any googling surprisingly.

I noticed this only after upgrading from angular 5 to angular 7 and one of my e2e tests that relied on my general error handler started failing.

The only workaround I found was to have something like this at the top of the error handler's handleError() method like this:

    while(error.rejection) {
      error = error.rejection;
    }

but...

1. I'm quite sure there's a better way - now I have to type error as any
2. I'm not sure if there are any other situations that will require unwrapping (e.g. from observables?).

Either way, if this was some kind of intentional feature, it's definitely a gotcha that I think should be mentioned (with the RIGHT way to handle it) in the doc link I pasted.

🔬 Minimal Reproduction

1. follow the docs and implement a global error handler and try to handle unhandled requests uniformly - something like this:

@Injectable()
export class SpiffyErrorHandlerService implements ErrorHandler {
  constructor(private injector: Injector, private snackBar: MatSnackBar) {}
  public handleError(error: Error) {
    if (error instanceof HttpErrorResponse) {
      if (error.status === 401) {
        this.snackBar.open(
          'Oops.  It looks like you tried to access a logged-in resource while logged out.  Please log in again.',
          '',
          { duration: 3000 }
        );
    }
  }
}

2. inject HttpClient

3. await this.http.get('/some-404-returning-url').toPromise();

🔥 Exception or Error

EXPECTED: error handler works, gets the HttpErrorResponse, and shows the snackbar
ACTUAL: the HttpErrorResponse is on error.rejection instead of right on error.

🌍 Your Environment

Angular Version:

Angular CLI: 7.1.2
Node: 10.14.2
OS: linux x64
Angular: 7.1.3
... animations, common, compiler, compiler-cli, core, forms
... http, language-service, platform-browser
... platform-browser-dynamic, router, service-worker

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.10.7
@angular-devkit/build-angular     0.10.7
@angular-devkit/build-optimizer   0.10.7
@angular-devkit/build-webpack     0.10.7
@angular-devkit/core              7.0.7
@angular-devkit/schematics        7.1.2
@angular/cdk                      7.1.1
@angular/cli                      7.1.2
@angular/flex-layout              7.0.0-beta.19
@angular/material                 7.1.1
@ngtools/webpack                  7.0.7
@schematics/angular               7.1.2
@schematics/update                0.11.2
rxjs                              6.3.3
typescript                        3.1.6
webpack                           4.19.1
    

Anything else relevant?