Tuesday, June 17, 2014

Testing is just "as per requirements" right?

A couple of weeks back, I was witnessed some brilliant observations by testers on Twitter that "testing is about more than as per requirement".  [I believe this was started by Michael Bolton, but I can't now find the originating Tweet].

This obviously at first is a very difficult idea to get to get your head around for some testers.  Lets face it most of our test ideas, especially scripts, are derived from these requirements.  And when we have a project without much in the way of requirement, it's quite unnerving, because we feel we're operating in a vacuum, and don't know exactly how to start.

But of course, requirements are fallible and prone to a certain type of error themselves if we take them as the only source of gospel truth.

There is an example of this which I really hope people are familiar with - if you've not watched it yet, can I please encourage you to watch this video of Spinal Tap's Stonehenge.

The real Stonehenge

If you're not familiar with it, here's the story ... Spinal Tap are a controversial (and fictional) British rock band.  For one of their songs, dedicated to the monument and druids of Stonehenge, they decide to have a prop for their act the represents the ancient stones.  So they draw a design, which their manager passes to a production company.

Stonehenge Design - your requirements, if you will

So off the design goes, until the production company comes back to the manager with what they've built.

Stonehenge Prop - are you telling me this is it?

The manager thinks it's wonderful, until he says "this is just the prop yeah"?  The production company says that no, this is it.  They built to design, 18 inches by 18 inches.  Someone it seems meant it to be 18 feet by 18 feet.  Yes, there was a fundamental flaw in those requirements.

The manager (god bless him) tries to pass off the prop, and the band end up seeing it for the first time during their song, bewildered about just why they have a version of Stonehenge that's in peril of being trambled by a dwarf ...

Even next to a dwarf, this monument does not impress

There's a serious point to this, if you hand someone a design, and tell them "just build this", you're going to probably get exactly what you asked for.  But it may not always be what you wanted.

Short of having accurate requirements or being a mind reader, how can the production team really achieve this?  This is why although requirements are an important oracle, they're not the only one.  This is why many disciplines of testing, talk about needing to understand not just what the client wants (which really is the requirements), but why they want it.

Had a discussion with the band taken place, I'm hoping that the production company would have heard, "this is for our song Stonehenge, we want it to dominate the stage, and look really impressive as these dwarves dance around it".  It's at this point, handing over the design, the company might have gone "dominate the stage ... at 18 inches?", to query and probe what they've been asked for, and hopefully deliver exactly what the customer wanted.

Of course, had that happened, we'd have lost what for me is one of the funniest comedy moments of all time ...

1 comment:

  1. Like so many incidents in the film, it's based on a true story. Black Sabbath commissioned life-size replicas of Stonehenge without it occuring to them that the resulting monoliths would be far too large to fit on the stages they were playing.