Automated testing

TDD is a form of automated testing. This section lists some other popular types of automated testing and how they compare to TDD.

Integration tests

These tests check how two or more independent processes interact. Those processes could either be on the same machine or distributed across a network. However, your system should exercise the same communication mechanisms as it would in production, so if it makes HTTP calls out to a web service, then it should do so in your integration tests, regardless of where the web service is running.

Integration tests should be written in the same unit test framework that you use for unit tests, and all of the same rules about writing good unit tests apply to integration tests.

The trickiest part of integration testing is the orchestration code, which involves starting and stopping processes, and waiting for processes to complete their work. Doing that reliably can be difficult.

If you’re choosing to mock objects...