Stack Overflow http://stackoverflow.com/q/40166854/2587435

mocking-components.ts

@Component({
  selector: 'p-dataTable',
  template: `...`
})
class MockDataTable {
  @Input() value;

  @Input() selection;
  @Output() selectionChange = new EventEmitter();
}

@Component({
  selector: 'table-component',
  template: '<p-dataTable #table></p-dataTable>'
})
class MyTable {
  @ViewChild('table') table;
}

@Component({
  template: `
    <table-component #myTable></table-component>
  `
})
class TestComponent {
  @ViewChild('myTable') table;
}

describe('component: TestComponent', () => {
  beforeEach(() => {
    TestBed.configureTestingModule({
      imports: [ ReactiveFormsModule ],
      declarations: [ TestComponent, MyTable, MockDataTable  ]
    });
  });

  it('should find elements', async(() => {
    let fixture = TestBed.createComponent(TestComponent);
    let component = fixture.componentInstance;
    fixture.detectChanges();

    console.log(`DATATABLE: ${component.table.table}`);
  }));
});