atomic test.ts

describe('placement="left"', () => {
  let windowEl;
  beforeEach(() => {
    const fixture = createTestComponent(`<div ngbTooltip="Great tip!" placement="left"></div>`);
    const directive = fixture.debugElement.query(By.directive(NgbTooltip));

    triggerEvent(directive, 'mouseenter');
    fixture.detectChanges();
    windowEl = getWindow(fixture.nativeElement);
  });
  it('should have tooltip css class', () => {
    expect(windowEl).toHaveCssClass('tooltip');
  });
  it('should have bs-tooltip-left css class', () => {
    expect(windowEl).toHaveCssClass('bs-tooltip-left');
  });
  it('should bind the tooltip text', () => {
    expect(windowEl.textContent.trim()).toBe('Great tip!');
  });
});