@Directive({
  selector: "[app-key-press]"
})
export class KeyupDirective {
  @HostListener("keyup", ["$event"]) onKeyUp(event: KeyboardEvent) {
    console.log(event);
  }
}

directive.spec.ts

describe('ComponentDirective', () => {
  // let component: MaroBaseComponent;
  let fixture : ComponentFixture<MaroDialogComponent>;
  it('should create an instance', () => {
    const directive = fixture.componentInstance.gdComponent;
    expect(directive).toBeTruthy();
  });
});