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Understanding the null result

What not failing a test doesn’t mean

Imagine you were in a world where something was wrong.

I know it’s a stretch, but stay with me, I know you can do it.  I believe in you.

Perhaps your website has a button of the wrong color. Or you there are records that aren’t showing up in your database query.

You’d probably write (or have your tech people write for you) a test. Perhaps they’d insert an “assert” into the code base.

If the test doesn’t fail or the assert doesn’t trigger?

What does this mean?

What it does not mean is there is no problem. The button hasn’t magically and retroactively become the right color. The query result hasn’t become correct.

What it means is that you need to look elsewhere for the cause of the problem.

I’ve never met a programmer that had had any difficulty understanding this. In fact, I’ve never come across one that needed it explained. It’s truly obvious.

On the other hand, when I go to a doctor with a complaint (a “symptom”), and they order a diagnostic that comes up “fine,” they seem to think it means that I am fine. That my symptoms and complaints somehow don’t matter or will go away or something. I’ve rarely come across a doctor that seems able to understand it. Somehow it is far from obvious.

I wish more doctors had first become programmers.

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Written by Russell Brand

Russell has started three successful companies, one of which helped agencies of the federal government become very early adopters of open source software, long before that term was coined. His first project saved The American taxpayer 250 million dollars. In his work within federal agency, he was often called, “the arbiter of truth,” facilitating historically hostile groups and factions to effectively work together towards common goals

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