Devnology Podcast 021 - Nat Pryce on Growing software with Tests

Nat Pryce is an early adaptor of eXtreme Programming and a
contributor to several open source libraries and tools supporting
Test-Driven Development, like jMock. In this episode we discuss
several topics from the book 'Growing Object-Oriented Software,
Guided by Tests' that he wrote together with Steve Freeman. We
talk about the 'Londen-style' of Test-Driven Development,
using mock objects to drive your design, listening to your tests
and dependency injection.


Nat's personal blog 'Mistaeks I Hav Made' is on
http://www.natpryce.com/ and you can follow him on twitter via
@natpryce.


This interview is recorded on June 14th at the Software Practice
Advancement conference (spa2011) in London. Interview by
@freekl and @arnetim. Audio post-production by @Mendelt.
Links for this podcast:

The roots of the 'Londen-style' of Test-Driven Development
can be traced back to the eXtreme Tuesday Club (XTC). A
weekly London (pub) meeting that started more than 10 years ago.

On his blog Nat visualizes different kinds of tests that
drive the design of a software system.

In the podcast we discuss the blogpost 'Whose domain is it
anyway?' of Dan North.

Nat completed his PhD thesis in 2000: 'Component Interaction
in Distributed Systems'. A lot of his thoughts on
object-orientation and messaging between objects and peers that
is described in the book, can be traced back to his early
research.

In order to improve the testability of your software, Steve
and Nat propose to apply the Ports and adapter architecture
from Alistair Cockburn. You can read more on this subject on the
wiki of Alistair.

Use Hamcrest Matchers to improve the readability of your
tests: learn more from this tutorial.

While the use of Dependency Injection is widely spread in the
software engineering community, Nat considers applying this style
harmful. On his blog you can read more of his thoughts on this
subject.

In 2004 Steven and Nat published the article 'Mock Roles, not
Objects' in which they introduces jMock.

MultithreadedTC: a framework that can be used to test
concurrent Java applications.