Angular Unit Test with MockBackend

import { inject, TestBed } from '@angular/core/testing';
import { BaseRequestOptions, Http, Response, ResponseOptions } from '@angular/http';
import { MockBackend, MockConnection } from '@angular/http/testing';
import { UserService } from './user.service';
import { serialize } from '@angular/compiler/src/i18n/serializers/xml_helper';

const mockResponse = [
  {
    'id': 1,
    'name': 'Leanne Graham',
    'username': 'Bret',
    'email': '[email protected]',
    'phone': '1-770-736-8031 x56442',
    'website': 'hildegard.org',
  },
  {
    'id': 2,
    'name': 'Ervin Howell',
    'username': 'Antonette',
    'email': '[email protected]',
    'phone': '010-692-6593 x09125',
    'website': 'anastasia.net',
  }
];
describe('UserService', () => {

  beforeEach(() => {
    TestBed.configureTestingModule({
      // imports: [HttpModule],
      providers: [
        BaseRequestOptions,
        MockBackend,
        {
          provide: Http,
          useFactory: (backend, options) => new Http(backend, options),
          deps: [MockBackend, BaseRequestOptions],
        },
        UserService,
      ],
    });
  });

  let service;

  describe('getUsers', () => {

    beforeEach(inject([MockBackend, UserService, Http], (mockBackend: MockBackend, service: UserService, http: Http) => {
      service = new UserService(http);
      expect(service).toBeTruthy();

      mockBackend.connections.subscribe((connection: MockConnection) => {
        connection.mockRespond(new Response(new ResponseOptions({
          body: JSON.stringify(mockResponse),
        })));
      });
    }));

    it('should be covered', inject([UserService, Http],
      (userService: UserService, http: Http) => {
        service = new UserService(http);
        expect(service).toBeTruthy();
      }),
    );

    it('should get all users with IUser properties', inject(
      [UserService],
      (userService: UserService) => {
        userService.getAllUsers().subscribe(users => {
          users.forEach(user => {
            expect(user.email).toBeDefined();
            expect(user.name).toBeDefined();
          });
        });
      }),
    );
  });

  describe('getUser', () => {

    beforeEach(inject([MockBackend], (mockBackend: MockBackend) => {
      mockBackend.connections.subscribe((connection: MockConnection) => {
        connection.mockRespond(new Response(new ResponseOptions({
          body: JSON.stringify(mockResponse[0]),
        })));
      });
    }));

    it('should get an user with ICountry properties', inject(
      [UserService],
      (userService: UserService) => {
        userService.getUser(1).subscribe(user => {
          expect(user.email).toBeDefined();
          expect(user.name).toBeDefined();
        });
      }),
    );
  });

});