Colección burlona de Firestore en TestBed angular
Me gustaría escribir una prueba unitaria para mi componente que usa Firestore y encontré un problema con la burla de la colección Firebase.
SUT
export class TobjectsListComponent implements OnInit {
...
constructor(private db: AngularFirestore) {
this.tobjectDatabase = new TobjectDatabase(db);
}
...
}
export class TobjectDatabase {
/** Stream that emits whenever the data has been modified. */
dataChange: BehaviorSubject<TObject[]> = new BehaviorSubject<TObject[]>([]);
get data(): TObject[] { return this.dataChange.value; }
constructor(private db: AngularFirestore) {
this.db.collection<TObject>('tobjects').valueChanges()
.subscribe(data => { this.dataChange.next(data); });
}
}
PRUEBA
class AngularFirestoreMock extends AngularFirestore {
public collection<TObject>(name: string, queryFn?: QueryFn): AngularFirestoreCollection<TObject> {
const ref = this.firestore.collection('tobjects');
if (!queryFn) { queryFn = (ref) => ref; }
return new AngularFirestoreCollection<TObject>(ref, queryFn(ref));
}
}
describe('TobjectListComponent', () => {
let component: TobjectsListComponent;
let fixture: ComponentFixture<TobjectsListComponent>;
beforeEach(async(() => {
TestBed.configureTestingModule({
imports: [MaterialModule],
declarations: [TobjectsListComponent],
providers: [{ "provide": AngularFirestore, "useValue": AngularFirestoreMock }],
schemas: [CUSTOM_ELEMENTS_SCHEMA]
})
.compileComponents();
}));
beforeEach(() => {
fixture = TestBed.createComponent(TobjectsListComponent);
component = fixture.componentInstance;
fixture.detectChanges();
});
it('should create', () => {
expect(component).toBeTruthy();
});
});
Prueba de funcionamiento
Una vez que ejecuto la prueba me sale un errorTypeError: this.db.collection is not a function
De la información de seguimiento de la pila, puedo leer que el error tiene un origen en esta línea y carácterthis.db.**c**ollection<TObject>('tobjects').valueChanges()
enTobjectDatabase
clase.
TypeError: this.db.collection is not a function
at new TobjectDatabase (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/src/app/tobjects-admin/tobjects-list/tobjects-list.component.ts:82:13)
at new TobjectsListComponent (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/src/app/tobjects-admin/tobjects-list/tobjects-list.component.ts:24:28)
at createClass (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core.es5.js:10933:1)
at createDirectiveInstance (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core.es5.js:10764:22)
at createViewNodes (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core.es5.js:12212:34)
at createRootView (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core.es5.js:12107:1)
at callWithDebugContext (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core.es5.js:13493:26)
at Object.debugCreateRootView [as createRootView] (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core.es5.js:12810:1)
at ComponentFactory_.webpackJsonp.../../../core/@angular/core.es5.js.,ComponentFactory_.create (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core.es5.js:9872:26)
at initComponent (http://localhost:9876/_karma_webpack_/webpack:/C:/git/volago2/node_modules/@angular/core/@angular/core/testing.es5.js:889:1)
Que pasa ¿Cómo podría burlarme de esta colección?