Testing our App

One primary advantage of using TypeDI, and Dependency Injection in general, is it greatly improves your ability to test individual components in isolation, by providing them with different values and implementations than would normally be present in your app.

For instance, consider the implementation of the HTTP server in the previous example. In testing, we may not want it to actually create a HTTP server, though we would want it to ensure it creates a HTTP server successfully.

note

For the examples below, we'll be making use of Jest. Tests are written in an easy-to-follow format.