Section 33.1. Test Infecting

33.1. Test Infecting

Emily, pair programming with Neo, altered RentEz in small steps to pass the growing number of Fit tests, doing this for each test in turn, where needed. They had been getting familiar with agile development techniques and wanted to get more experience with pair programming (see the following Note).

They added a name property to those GUI components that needed to be accessed to enable the tests to run through the user interface (see Chapter 32). They took less time than they expected to make the changes for the first test luckily, as it was a rather mechanical task. As Emily commented, "At least there's a low chance of introducing errors, because we're simply adding simple code to set names and not otherwise changing what's there."

Note

Pair programming [Wil02] is an effective technique to develop high-quality software that combines development and review in a single process. While one person is using the keyboard, the other is actively engaged in watching, thinking, and giving feedback. Together, the two are continuously considering and discussing various approaches to unit tests, code, and design.

Although it appears that less work will be done with two people working together, experimental evidence indicates that this technique produces higher-quality systems, thus reducing longer-term costs owing to bugs and badly structured systems.