Debugging Flaky Tests in Angular with Jasmine and Karma on CI/CD Pipeline
I'm working with a frustrating scenario with flaky tests in my Angular application that I'm running using Jasmine and Karma on our CI/CD pipeline. Some tests intermittently unexpected result without any clear reason, and on rerunning the same tests, they often pass. One example is a basic component test that checks if a button click triggers a method call: ```typescript it('should call the onClick method when the button is clicked', () => { const button = fixture.debugElement.query(By.css('button')); spyOn(component, 'onClick'); button.triggerEventHandler('click', null); expect(component.onClick).toHaveBeenCalled(); }); ``` This test occasionally fails with the behavior message: `Expected spy onClick to have been called...` even though I can see in the console logs that the click event is firing properly. I've ensured that I'm using the latest versions of Angular (12.2.0), Jasmine (3.7.0), and Karma (6.3.4). I've tried adding `fakeAsync` and `tick()` to handle any asynchronous operations, but it doesn't seem to make a difference. Here’s how I structured the test: ```typescript it('should call the onClick method when the button is clicked', fakeAsync(() => { const button = fixture.debugElement.query(By.css('button')); spyOn(component, 'onClick'); button.triggerEventHandler('click', null); tick(); expect(component.onClick).toHaveBeenCalled(); })); ``` This also intermittently fails. Additionally, I confirmed that other tests running before this one are not affecting the state of this component. I've tried running tests in both Chrome and Firefox, as well as in headless mode, but the flakiness continues. Do you have any recommendations on how to stabilize these tests or debug issues within the CI/CD environment? Any insights into configurations or best practices for testing components in Angular would be greatly appreciated.