Comment by lgriffith | Hacker News Reader

Comment by lgriffith | Hacker News Reader

Interesting idea but....

Looks like meeting that goal would constrain you to write code to be used by a robot and not by a human. There may be many cases where this is both doable and acceptable to the end user. So no problem with that.

I am greatly challenged to see how this could be done for a highly interactive, visually oriented, subtle pattern generating response to user input, type application. Computers are still not as bright as earth worms when it comes to generalized pattern recognition. Which means we programmers are about as bright as earth worms when it comes to writing such code.

How then could computers automatically test all the software reactions to the wonderful and totally unpredictable behavior of mere humans as they interact with your software? The test cases would expand to consume all the resources available for development. All you would get done is writing all but impossible test cases. At least you wouldn't ship bugs.

This does not consider the explosion of combination and permutations of inputs that prohibits exhaustive testing that no matter how many systems you run tests on.

It would be much easier and cheaper to go out of business. Your certainty of being free of shipped bugs would be much better than one in a million.

As I noted elsewhere in this thread (http://news.ycombinator.com/item?id=475391), this article is not merely about automated tests. The author says that his company is using continuous deployment because it lets live, human end users bang on the code, as quickly as possible, in bite-sized chunks that can more easily be rolled back and fixed.

Then why do such an exhaustive automated test?

Why not have your local tests, automated or not, cover the common cases and error conditions to catch programmer stupidities? Then let the actual humans do the strange corner cases.

If your design is even close to correct, testing repeatedly tested code is pointless. If your design is corrupt and your implementation is sloppy, no amount of testing is going to save your ass.

I do very rapid turns and I am a one man team. I can turn my system in less that 30 minutes and have the user testing it in a live situation on the other coast. If I want 10 turns a day, I can easily do it. Low coupling, high cohesion, clean correct design, and disciplined implementation makes it possible.

I agree that doing things in small chunks is a great way to do it but doing the equivalent of a weeks worth of global automated testing for each small change seems like a silly exercise. That is except for the server hardware salesmen and system admin people.

The sales commissions and payroll look rather good. The production of real value is questionable. Bang for the buck is as important for testing as it is in any other part of product development.

I think the source of your confusion is that you're a one man team. You don't have to solve problems that 20-man teams have to face. At least half of all the code I depend on is code I do not understand, so I have to depend on its tests, and I have to make the same promise to consumers of my code. If my change breaks code someone else wrote that I didn't foresee, I am depending on his tests to tell me what I screwed up.

Maybe the problem is that you have the 20-man team. There is no coherence in the code. The design is wrong, coupling is too high, and the module cohesion is too low. The large team makes certain that is the case no matter how "tight" (aka heavy) your quality control process.

I have found from working in large teams, there is a core four who get things done. The rest are simply dead weight dedicated to shuffling paper and attending meetings. At best, they do nothing. At worst they create more work than they do.

Use the right four and dump the other sixteen. You will get at least ten times more productivity and ten times higher quality without even breaking a sweat. If you don't have the right four, you are hosed from the start.

This works fine if you are tackling a problem that can be sufficiently addressed by 4 developers. Depending on the size and scale of the problem you are trying to suggest and the time line required for delivery you may need a larger team.

When you begin to take that into account you realize you have to find ways for the larger team to work together and still produce a quality product. Hence the techniques being used by the author and other companies out there trying to address similar problems.

"...you have to find ways for the larger team to work together and still produce a quality product. "

I am not sure its possible. The communication overhead of so many linkages forces incoherence. The resultant incoherence forces still more additions to process and body count. That adds still more communication overhead. The result is still more incoherence - not less. If something is "finished", its simply because time, money, resources, and toleration ran out. The end result was simply called "done".

Maybe that is the best we can do but I am hard pressed to call products produced that way quality products. See Vista et.al. for instructive detail.

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