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Showing posts from February, 2012

On a Hiding to Nothing

Is it a bug when you're offered the chance to see something similar to nothing and, when you take it, nothing is displayed? Or is it a bug to be offering the chance in the first place? Image:

Sheet Happens

You don't have to look very hard to find definitions of quality. Some of them aren't very good ( boom! boom! ) and one with a lot of currency runs along these lines:  Quality is value to some person (who matters) in this case quoted from James Bach's Rapid Software Testing slides.  Here's the price ticket for toilet roll I saw in the supermarket this morning. It adds a new dimension to the phrase spending a penny :  Is there a quality issue here? I'm not sure whether I matter much to Tesco and it's arguable whether any value was lost by the use of this unfortunate abbreviation - I still bought some toilet paper - but i f your customers are laughing at you rather than with you, there's probably a quality issue somewhere. Image: winnond /

Defect Three

Purely by chance I encountered three takes on perfection in the space of a couple of days. "Perfection", Run DMC said , "is quite essential". A laudable aspiration but, as their later career showed handsomely, hard to achieve. Compromise has a lot of very persuasive arguments. "This software is bug-free. It is perfect", Fast Company said of the Space Shuttle's control system , "as perfect as human beings have achieved ... the last three versions of the program - each 420,000 lines long - had just one error each." Skipping over how they knew that there was just one error , and why they didn't fix it, NASA had obvious reasons to strive for perfection, including the need to certify "that the software will not endanger the shuttle" before launch. Their approach was to be meticulous in the meta-work that supports software production as well as the production itself. But they still had errors. "We test", Weinberg s

Bogof Testing

We all like a bargain and, if there was such a thing, we'd tuck into the free lunches with gusto too. But bargains needs to be viewed with caution and free lunch is usually only about half right - it probably is lunch. Automated testing is often thought to be a bargain or a free lunch but even limited experience will have shown you that it's not something for nothing and not even always cheap, especially in terms of maintenance. You should think carefully about whether regression tests are appropriate , what you hope to achieve, how, using what resources and attempt some level of cost/benefit analysis (using whatever data, estimates, gut feeling you have available) before you start on an automation project to try to maximise its value. But existing infrastructure can have unexploited value . For example, it is sometimes possible to double up regression test suites and test something other than what was originally intended. In my company we have both a traditional sof

Wrong is not not Right

I saw a blue being from another dimension clawing its way through the ceiling the other day. If only. The building I work in is being redecorated and on the way to the canteen  I noticed that the painters had covered a smoke detector with a rubber glove. You don't need to be a health and safety officer to realise that this is not standard policy and potentially risky. But, paint fumes can set off smoke detectors and there were plenty of people around and there are many other smoke detectors in the building and the lack of other detectors covered with gloves suggested that decorators would be likely to remove it when they'd moved further down the building so I decided to do nothing about it. A clear spec violation, but mitigated by other factors. A reasonable short-term solution to an acute issue, but on the way home I still walked that way and checked that it had gone. You'll sometimes hear testers described as pedantic  and it's true that the detail and p