In this chapter, we used an application that we created using the Angular CLI, added tests to it by using Jasmine, and ran it using Karma. We saw how we can test our application using isolated unit testing, integration testing, and end-to-end testing. We also measured the code coverage of our application and measured the percentage of code that's covered using our tests. We also replaced our Jasmine and Karma setups with Jest and ran a snapshot test of one of our components.
After completing this chapter, you should be writing code that is very close to being bug-free. Often, developers have the opinion that, since manual testing has already been done on the feature code, it's not required to write tests, but more often than not, they usually end up getting bugs in it. There are possibilities that a very minute change ends up breaking the application. This can...