Angular Testing: fails to resolve all parameters for Store: (?, ?, ?)

Question

I am trying to declare my ngrx/Store into the spec file for testing a container component. So I import the store first and inside the beforeEach do the following:

      import {Store} from '@ngrx/store';

       beforeEach(async(() => { 
        TestBed.configureTestingModule({
              declarations: [NotificationsComponent, NotificationsDevicesComponent, 
               ToArrayPipe, OrderByDate, TimezoneFormatPipe],
              providers: [{ provide: Store, useClass: Store }]
            })
              .compileComponents().then(() => {
                fixture = TestBed.createComponent(NotificationsComponent);
                component = fixture.componentInstance;
                el = fixture.debugElement;

                fixture.detectChanges();
              });
          }));

But I got the error from the heading fails to resolve all parameters for Store: (?, ?, ?).

Any ideas?

Many thanks

The cannot resolve parameters for foo: (?, ?) usually means your dependency injection is not working properly (circular dependencies, bad imports, bad exports, etc). The question marks will indicate the dependencies. Sometimes it'll be like (FooService, BarService, ?), which means the third dependency is the one with the problem. — Lansana Camara
Try importing the 3 services they you're trying to inject into Store directly from their file, not from a barrel, if that's what you're doing. — Lansana Camara

Anurag Singh Bisht Anurag Singh Bisht · Accepted Answer · 2017-08-03T11:55:58

I have used ngrx and tested store

Here are the steps I followed -

Imported StoreModule and Store

import { StoreModule, Store } from '@ngrx/store';

Imported my reducers
```
import { reducers } from './reducers';
```

Added StoreModule in my TestBed

TestBed.configureTestingModule({
  imports: [
    StoreModule.forRoot({
      categories: reducers // My reducers
    })
  ],

Defined store variable
```
let store: Store<CategoryState>;
```

Initialized store

beforeEach(() => {
  store = TestBed.get(Store);

  spyOn(store, 'dispatch').and.callThrough();

  fixture = TestBed.createComponent(CategoryListComponent);
  component = fixture.componentInstance;
  fixture.detectChanges();
});

After that you can use store in your test cases.

Angular Testing: fails to resolve all parameters for Store: (?, ?, ?)

1 Answers