Testing components and services that make HTTP requests requires mocking to avoid actual API calls and ensure tests run fast and reliably. With over 12 years of Angular development experience since 2014 and as the creator of CoreUI, I’ve written extensive test suites for HTTP-based services. Angular provides HttpClientTestingModule and HttpTestingController specifically for mocking HTTP requests in tests. This approach allows you to verify requests are made correctly and control response data for different test scenarios.