Professional Visual Studio 2013

Chapter 11Unit Testing

WHAT’S IN THIS CHAPTER?

• Generating a test harness from existing code
• Making assertions about the behavior of your code
• Executing custom code during test life-cycle events
• Creating data-driven tests
• Testing private members and code contracts
• Managing lists of tests

Application testing is one of the most important parts of writing software. Research into the costs of software maintenance have revealed that a software defect can cost up to 25 times more to fix if it makes it to a production environment than if it had been caught during development. At the same time, a lot of testing involves repetitive, dull, and error-prone work that must be undertaken every time you make a change to your code base. The easiest way to counter this is to produce repeatable automated tests that can be executed by a computer on demand. This chapter looks at a specific type of automated testing that focuses on individual components, or units, of a system. Having a suite of automated unit tests gives you the power to verify that your individual components all work as specified even after making radical changes to them.

Visual Studio 2013 has a built-in framework for authoring, executing, and reporting on test cases. This chapter focuses on creating, configuring, running, and managing a suite of unit tests as well as adding support to drive the tests from a set of data.

YOUR FIRST TEST CASE

Writing test cases is not easily automated because the test cases must mirror the ...