Test Driven Development (The Addison-Wesley Signature Series)
Kent Beck

£20.04

buy from amazon

The premise of this book is to design organically (No grand plans).

Programming is reduced to the sequence

• write a test
• write code that passes the test
• clean up that code (remove any duplication)

Much of the book is about getting into and keeping a good programming mindset - one nice tip is to always leave a failing test at the end of the day (this give you something concrete to start on the next day).

This book has changed the way I work (a bit).

I will write more tests, and sometimes I'll write tests first.

But I'm not quite convinced that testing everything first is worthwhile - especially as I often work with legacy code which is hard to test.

Maybe I'm less enthused by the book because it's aimed at users of Java - much of it doesn't quite translate to PHP and Drupal (loosely typed and only partially object oriented). 

The preface and first chapter are good - then the examples get really slow - skip ahead to part III. The patterns for test driven development are really useful.