Automated testing remains a cornerstone of effective software development. For front-end tests we can argue whether the distribution of different test types should be the classic test pyramid or whether it should be a trophy shape. In either case, though, teams should focus on component testing because test suites should be stable and run quickly. Instead, what we're seeing is that teams forgo mastering component testing in favor of end-to-end browser-based testing as well as very narrowly defined unit tests. Unit tests have a tendency to force components to expose what should be purely internal functionality, while browser-based tests are slow, more flaky and harder to debug. Our recommendation is to have a significant amount of component tests and use a library like jsdom to run the component tests in memory. Browser tools like Playwright of course still have a place in end-to-end tests, but they shouldn't be used for component testing.
