create a mock rest service which doesn't report errors

npm/ng-packs/packages/core/testing/src/lib/services/index.ts

@@ -0,0 +1 @@
+export * from './mock-rest.service';

npm/ng-packs/packages/core/testing/src/lib/services/mock-rest.service.ts

@@ -0,0 +1,21 @@
+import { ABP, CORE_OPTIONS, EnvironmentService, RestService } from '@abp/ng.core';
+import { HttpClient } from '@angular/common/http';
+import { Inject, Injectable } from '@angular/core';
+import { Observable, throwError } from 'rxjs';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class MockRestService extends RestService {
+  constructor(
+    @Inject(CORE_OPTIONS) protected options: ABP.Root,
+    protected http: HttpClient,
+    protected environment: EnvironmentService,
+  ) {
+    super(options, http, environment, null);
+  }
+
+  handleError(err: any): Observable<any> {
+    return throwError(err);
+  }
+}