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Test-Driven Development is Stupid

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Re: Test-Driven Development is Stupid

#31

Post by ayberkt »

> Let me emphasize: you write the test cases for your program, and then you write your program. You are writing code to test something that doesn't even exist yet. I am not rightly able to apprehend the kind of confusion of ideas that could provoke such a method.

I don't understand this. What is so absurd about specifying facts about the program you will write? When we have tools that can prove facts, we will be doing formal specifications instead of random sampling. But still, testing is a way of statistically specifying facts about your program, for which it seems sensible to be written before the program.

Re: Test-Driven Development is Stupid

#32

Post by struppi »

If you're doing TDD (or software development) like this, you're doing it wrong. Yes, yes, I know. No True Scotsman [1]. But when many - I mean LOTS OF - people say "I get benefits form [Technique]", you can't just say: "It cannot work. I tried it, it sucked.".

I mean, you can say that. But doing so makes you look... ignorant - at best. You know, there is a possibility that you just got it wrong.

So, many great programmers say that they get benefits from TDD. They get benefits. Not the suits. Not their co-workers. They.

TDD is hard. I had to learn it and practice it. And I'm still learning and practicing it, even though I'm now also teaching it to others and helping teams implement it. But I get benefits from it. Writing tests helps me to think about problems and to actually improve my designs [2]. And writing tests helps me to know when to stop - To not gold-plate my designs.

Sorry, but this "article" is just an angry rant, with no real arguments. Please, don't give up on TDD early because of rants like this. If you have any questions about TDD or need help getting started, feel free to ask (here or in private - you'll find my email address in my profile)...

[1] http://davidtanzer.net/no_true_scotsman_in_agile

[2] But you have to refactor ruthlessly. And learn and practice refactoring, which is hard.

Re: Test-Driven Development is Stupid

#33

Post by ramblerman »

TDD is truly cult like in it's extreme. Usually it's managers and slightly weaker technical folk with a scrum certification that spew the absolutist TDD path.

I'm a contract java developer and I know how to 'play the game'. The hypocrisy in the amount of fizbuz clones I've written in a TDD fashion on interviews, to then see the production code has no little to no unit tests.

I once got negative feedback on an interview because I wasn't TDD enough after expressing the opinion that TDD works great for most use cases but there are limits, e.g. positioning of a front end element isn't always best done TDD. The guy interviewing was non technical and of course any dissent to TDD meant I was a bad fit.

Anyways - end rant. Like I said I just learnt to play the game.

Re: Test-Driven Development is Stupid

#35

Post by pjc50 »

Buried in the rant are a couple of sound points:

>- You're trying to make a design before you learn anything about it.

>- People write something one way, but then are afraid to change it because they'll have to rewrite the testing code that goes along with it.

Both of these suggest tests of the wrong granularity; that people are, as he says, writing silly little fencepost error checks for every single function.

Re: Test-Driven Development is Stupid

#36

Post by acaloiar »

> "Trying to improve software quality by increasing the amount of testing is like try[ing] to lose weight by weighing yourself more often."

Giving the benefit of the doubt that this quote is in fact an accurate metaphor – to begin with this quote is to begin with the assumption that TDD's single motivation is improving software quality. TDD is a fantastic practice for ensuring conformity to a specification; which one might describe as software's correctness. A more objective metric than "quality".

Re: Test-Driven Development is Stupid

#37

Post by zeveb »

mabbo wrote: post #6

> I am against writing unit tests in general, since experience shows that they actually prevent high-quality code from emerging from development And he's lost me in his first sentence. Unit testing, good unit testing at least, is not just about developing as it is about preventing regressions. A unit test that runs on every build ensure that something is true and that it stays true forever.

I think I see part of his point, though. By its nature, a unit test is (often, albeit not necessarily) tightly coupled with the thing it is testing--which means that anyone who changes the implementation must change the test, which increases the complexity of code changes.

I know that in my own work, the single most important thing for me is to be able to massively refactor, restructure and redesign my and others' code, as I'm working with it (this is probably why I like dynamic languages and macros so much, and probably why I benefit from static typing so much); anything which gets in the way of deleting, reorganising, clarifying, duplicating, altering, reducing and shifting code is going to slow me down and make the resulting code worse.

Perhaps, though, there is a middle ground: while the internals of a library must be free to mutate, the external interface ought not to change nearly as much. Perhaps all unit tests should be written to test the external interface, not the internal details. That might also help avoid the tests-which-test-that-the-code-does-what-it-does disease.

I do really appreciate tests, and they do help detect and prevent certain types of regressions.

Re: Test-Driven Development is Stupid

#38

Post by auggierose »

It's not really a rant, it is a very strongly communicated opinion. And I agree with a lot of it.

I don't mind writing a few test cases during or after I am done with my work. This is mostly to protect someone (including me) to change my perfect design after I have found it, though ;-)

Re: Test-Driven Development is Stupid

#39

Post by lmorris84 »

> I am against writing unit tests in general

> How often have you seen a program crash? If it was developed by a large software company, chances are it was written using TDD. Clearly, TDD is not a magic bullet. So, TDD does not "prove your code works".

> Developing software is like a painting commission

Several reasons I gave up a third of the way in. I rarely write tests first, but I can appreciate that it works for plenty of people - my brain just doesn't work that way.

It's hard to take anything in this article seriously because of the nerdrage and the dismissal of anything he disagrees with as "stupid".

Re: Test-Driven Development is Stupid

#40

Post by TeMPOraL »

mabbo wrote: post #20
reasonality wrote: post #9

Earlier quoted context omitted.

It depends what you're developing, and who you're developing with. If you're developing something which must work 100% every time or else someone will die, then unit tests are a must. If you're developing with people who break the build all the time, then unit tests are useful. Unit tests that aren't 100% up to date with the code are worse than no unit tests.

On the teams I've work on, pushing code that doesn't build and pass all unit tests is grounds for mocking. I have an alias in my zshrc file called "safepush" that runs [clean command] && [build command] && [test command] && git push If any piece doesn't succeed, the command stops. No push without unit tests passing.

And, as the article points out nicely, this basically prevents people from refactoring their code. In any nontrivial codebase, when you have a lot of tests, then what would have been 15 minutes of work rearranging class structure turns into a whole day of rearranging test cases to fit the architecture again.
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