Get started testing Angular 5 with Jasmine and Karma. This video covers basic testing component TDD concepts as well as 3rd party services like Firebase. https://angularfirebase.com/lessons/angular-testing-guide-including-firebase/
Jasmine: https://jasmine.github.io/
Testing Docs: https://angular.io/guide/testing
Great Article: https://medium.com/javascript-scene/tdd-the-rite-way-53c9b46f45e3