describe('calcTriangleArea', () => {
  beforeEach(async () => {
    await TestBed.configureTestingModule({
      imports: [AppComponent],
    }).compileComponents();
  });
  it('should return the area of a triangle', () => {
    const app = new AppComponent();
    expect(app.calcTriangleArea(3, 4)).toBe(6);
  });
});