Musings on Behaviour Driven Development

I've been following Behaviour Driven Development (BDD) from a distance, for a while and was reading a couple of good articles about it. A good introduction is one by Dan North.

http://dannorth.net/introducing-bdd/

As an advocate of Test Driven Development (TDD), I find sometimes it can make you focus on the finer detail at the expense of missing the bigger picture. Hopefully BDD can be used to fill this gap.
I'm all for closing the loop between QA/business analysts and developers. Using traditional approaches, it's inevitable that some things will be lost in translation.

I've had a brief look at Cucumber and conceptually I like what I see. However as my main skill set is in Java, I wasn't too enamoured in having to learn Ruby to get BDD benefits. Fortunately there are options. I like JBehave's approach to BDD. It's more amenable in the sense that the stories(specifications) are written in simple English and steps are written in Java in preference to Ruby.

A business analyst can write a number of stories in the normal BDD format in plan text files i.e. Given X, When Y Then X

For example:

• Given a refund request with a threshold of 10.0
• When refund request received for 20.0
• Then the alert status should be ON

Every step (Given, When, Then) is then executed by a JUnit test which can extract parameters from the step. So basically the acceptance criteria are always driven by the business analyst. There is little opportunity for ambiguity as a tight coupling will always be enforced between the specifications and its JUnit counterpart.

See http://jbehave.org/reference/stable/developing-stories.html for more information and examples.

I expect that the path to getting comfortable with BDD will be similar to TDD: writing lots of tests, some of them fairly bad, until over time we get a certain feeling for what's right or wrong develops.

My only reservation is that most of examples I've seen are relatively simple. I'd be interested in a real-life example especially in the potential complexity of stories.

I am sceptical but at the same time curious. But I see that by utilising a BDD approach the test fixtures and tests become self describing.  They exhibit meta data for the understanding of  the intentions and actions of the code. Anyone who's worked with me knows that documentation is the bane of my life. Anything that could make my life easier in that respect gets a thumbs up from me :).