Chapter 5: Preventing Bugs with Unit Testing

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Never stop testing, and your advertising will never stop improving.

—David Ogilvy, Confessions of an Advertising Man

Overview

Ogilvy made quite an impact on the advertising world (if you’re old enough, you may remember the Maxwell House percolator in time with the music, or the guy with the eye patch wearing Hathaway shirts), but if you change “advertising” to “software” his dictum applies equally well to development. Developers are recognizing that testing is not something to be left to other people, or to be done only at the end of a project. By integrating testing directly into your development process, you can produce more robust and error-free code. In this chapter, I’ll show you how to do that with unit testing. I’ll also introduce you to the basics of two related subjects: test-driven development and refactoring.

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