In this chapter we illustrated how to drive unit tests from a software design, identifying test scenarios in a systematic way that ensures the code is covered in all the right places. We also illustrated the use of "stunt services" and mock objects to isolate the code being tested; finally, we discussed driving unit tests deeper into algorithmic code that may benefit from finer-grained testing. Is there a way to get 95% of the benefit of the comprehensive unit testing we did in this chapter with significantly fewer tests? In the next chapter, we'll show how to do exactly that with controller tests. As you'll see, unit tests do have their place, but controller tests can often represent a smarter, more structured approach to application testing. 136 C H A P T E R 6 ? ? ? Conceptual Design and Controller Testing As you saw in Chapter 5, unit testing doesn't have to involve exhaustively covering every single line of code, or even every single method, with tests. There's a law of diminishing returns-and increasing difficulty-as you push the code coverage percentile ever higher. By taking a step back and looking at the design on a broader scale, it's possible to pick out the key areas of code that act as input/output junctures, and focus the tests on those areas.
The groundbreaking book Design Driven Testing brings sanity back to the software development process by flipping around the concept of Test Driven Development (TDD)-restoring the concept of using testing to verify a design instead of pretending that unit tests are a replacement for design. Anyone who feels that TDD is "Too Damn Difficult" will appreciate this book.
Design Driven Testing shows that, by combining a forward-thinking development process with cutting-edge automation, testing can be a finely targeted, business-driven, rewarding effort. In other words, you'll learn how to test smarter, not harder.
- Applies a feedback-driven approach to each stage of the project lifecycle.
- Illustrates a lightweight and effective approach using a core subset of UML.
- Follows a real-life example project using Java and Flex/ActionScript.
- Presents bonus chapters for advanced DDTers covering unit-test antipatterns (and their opposite, "test-conscious" design patterns), and showing how to create your own test transformation templates in Enterprise Architect.
