Chapter 4. Integration Testing

Chapter 3 covered unit testing and Test Driven Development, but there are times when you need to cross application boundaries and go beyond testing your application as a single, isolated unit. This is where integration testing comes in. Integration testing is very similar to unit testing, with a few major differences. The main difference is that integration tests are much more likely to access external systems such as databases or web services. An integration test would combine the two components and verify that they work together.