Comment by dasil003 | Hacker News Reader

Comment by dasil003 | Hacker News Reader

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First of all I agree with the idea that automated testing is not a guarantor of quality. Rather automated testing is one tool, along with exception notification, logging, and a fail-fast philosophy that each shines a light from a different angle to help overall quality. And if you need the strongest possible guarantees against failure then you have to go with a more fundamentally strict language such as Haskell.

But I think your comment misses out on the middle ground in common dynamic languages. What a good test suite does is reflect on code to document the intention of the author and provide an automated means of verifying that that intention was in fact fulfilled. Granted, test suites have bugs too, so a passing test does not guarantee there wasn't a bug, but the fact that you have two (hopefully) orthogonal descriptions of the code in question means that you stand a much better chance of actually teasing apart what happened when something blows up down the line. I've been saved and emboldened by my test suite enough in Ruby that I now consider it irresponsible not to have complete-ish coverage. I just see it as good code hygiene.

I just see it as good code hygiene.

I think it is necessary hygiene for Ruby. In dynamic language web apps, everything is so loosely coupled together by a mixture of conventions and magic strings (or symbols, if that makes you feel any better about them) that it's very easy for one of the strings to break without noticing.

But IMO you are mostly (perhaps 80%) working around an inadequacy in the tools. It is not a virtue in and of itself.

I'm in the odd position of having transitioned to working at a startup, writing Backbone / RoR, after having been a compiler engineer, and before that, in ~2006, the author of a server-side web app framework designed to be strongly typed throughout (using a custom language for control binding to achieve this goal). RoR is very error-prone and a lot of work by comparison, especially when interfaced with Backbone so that the UI doesn't need constant whole page round trips.

So many bits and pieces need to be glued together, from attr_accessible through to update params slicing, binding controls in JS, JBuilder json templates, the whole game of finding just the right elements with jQ and friends, so much busywork with so many opportunities for mistakes to creep in - so that tests are absolutely critical.

You are conflating Ruby with RoR. You start by saying "I think it is necessary hygiene for Ruby." but then go on to say "RoR is very error-prone and a lot of work by comparison" and "So many bits and pieces need to be glued together, from attr_accessible through to update params slicing..." -- that's Rails you're talking about. And I don't blame you for that. As a long-time Ruby developer, I can say with no qualms that Rails is a not a very good web framework, way too buggy and full of magic. But please don't conflate that with Ruby. Ruby with Sinatra is a hell of a lot cleaner and it's much easier to structure your code well.

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