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Best Heuristics


The Association for Software Testing is crowd-sourcing a book, Navigating the World as a Context-Driven Tester, which aims to provide responses to common questions and statements about testing from a context-driven perspective.

It's being edited by Lee Hawkins who is posing questions on TwitterLinkedInSlack, and the AST mailing list and then collating the replies, focusing on practice over theory.

I've decided to contribute by answering briefly, and without a lot of editing or crafting, by imagining that I'm speaking to someone in software development who's acting in good faith, cares about their work and mine, but doesn't have much visibility of what testing can be.

Perhaps you'd like to join me?

 --00--

"There are no best practices, really?"

The  context-driven testing principles do say that, yes, but not quite so baldly: 

There are good practices in context, but there are no best practices.

Context is crucial. An approach that works for you, for this problem, today might not work for me, or for an apparently identical problem, or on another day. You'd agree that you have seen this many times.

But you'd push back too because you have also seen the same methodology applied multiple times with great results. And that's fine. "No best practices" does not mean that no practice can ever be reused.

Tongue somewhat in cheek, I might ask whether you can be sure that those great results were definitely the best they could possibly have been, and in what way, and for who. A best practice cannot be bettered.

But that's a cheap shot and, while it does hit home, I wouldn't want to make this an argument about the semantics of superlatives.

For me, there are real, practical, benefits to taking the perspective that there are no best practices. The primary gain is that it can help us to make an informed choice, balanced across competing needs and constraints, given what we know at the time.

But, you'd say, when there's a nail in front of you, you'll hit it with a hammer. 

For sure, and often the default will be the right thing to do. But sometimes it won't. Sometimes there'll be a reason that the nail must stay half-out, must be knocked in only after some other event, requires a special hammer, requires new safety equipment, should be left to the person responsible for the whole row of nails (that you didn't notice), should be left for a new colleague so that they get experience, or some other relevant factor.

OK, you'd say, you can accept that but surely always considering the context is itself a best practice.  

And so I'm a hypocrite? I'd say that's a cheapish shot too, but I like your style! 

In fact, I've pondered that idea myself and I think I'd answer that there are occasions in which stopping to take account of the context might be the wrong thing to do. For example, in life-or-death situations where you must simply act.

However, even if you don't want to accept that there could never be a best practice, I hope you're persuaded that treating a lack of best practices as a heuristic could be valuable?

Yes, you'd say, but now you're wondering whether there are any best heuristics?
Image: https://flic.kr/p/2mEGrFg

Soundtrack: George Best 30 

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