The references I left out in my previous e-mail: [1] TDD leads to an architectural meltdown around iteration three - http://beust.com/weblog/2008/03/03/tdd-leads-to-an-architectural-meltdown-around-iteration-three/ [2] TDD Triage - http://web.archive.org/web/20120201002523/http://blog.objectmentor.com/articles/2009/10/08/tdd-triage
Philip On Sunday, 23 February 2014 22:51:16 UTC, Philip Schwarz wrote: > > In "TDD leads to an architectural meltdown around iteration three" [1] you > say: “Tests first” or “tests last” is unimportant as long as there are > tests." > > In "TDD Triage" [1] Robert Martin has a section called "Well, if you are > going to write some tests afterwards, why not write all tests afterwards?". > Here is what it says: > > "Well, first, there’s the > George-Williams<http://web.archive.org/web/20120201002523/http://www.google.com/url?sa=t&source=web&ct=res&cd=1&url=http%3A%2F%2Fcollaboration.csc.ncsu.edu%2Flaurie%2FPapers%2FTDDpaperv8.pdf&ei=WoTMSvSXMYSqtgfDnMjrAQ&usg=AFQjCNHk6TJnNC32UGD8cN65EWGjoQkTBA&sig2=pbzOxiSB7_HAOoBTyDqetQ> > study, > which showed that teams who are instructed to write tests afterwards, don’t > write tests at all. Of course this is human nature. Once you have the code > “working” why write tests? Writing tests for code that you believe works > feels like a waste of time. > > But that can be countered with sheer discipline. The real reason to follow > The > Three Laws of > TDD<http://web.archive.org/web/20120201002523/http://butunclebob.com/ArticleS.UncleBob.TheThreeRulesOfTdd> > and > write your tests first is that it greatly enhances the chances that every > line and every decision is tested. > > Code coverage is a sneaky metric. It is quite possible to create extremely > high levels of coverage without a single assert. I don’t need to tell you > that coverage without asserts is less than meaningful. When you write tests > first, your assertion coverage is very high. When you write tests after, > you assertion coverage simply cannot be that high. Even the most dedicated > and determined developer will make some coding decisions that block later > testability. When you write the tests first, this simply cannot happen. > When you write the tests first every coding decision you make *must* support > testability. > > Clearly writing the tests first forces an extremely high degree of > compatibility between the tests and the code. Writing the tests first also > means that your first thoughts about the code are from the point of view of > a user, not an author; and that also has benefits. > > So, *all else being equal*, test-first is clearly better than test-after." > Philip > > On Friday, 21 February 2014 21:47:44 UTC, Cédric Beust ♔ wrote: >> >> Not a big fan for multiple reasons: >> >> - TDD introduces a lot of churn, especially in the early phases of your >> coding. If you're beginning to work on a problem from scratch, you will >> most likely throw one or two initial implementations before reaching >> something you feel is acceptable as a v1.0. Writing tests for any version >> prior to this one is a waste of time. >> >> - TDD encourages myopic design. You are more focused on writing your code >> so it can pass trivial unit tests than thinking about how your overall >> design will fit with the rest of the code base. >> >> - TDD has high friction. If you are very zealous with TDD, every minor >> change in the code base will cause you to update tests. I'm okay with a >> little bit of that (it's the purpose of tests) but not to the extent that >> TDD promotes. >> >> - It overly privileges unit tests over functional tests, and my default >> position is that functional tests are more important (if I have the time to >> write a functional or a unit test and just one, I'll always go for >> functional because these tests have a direct impact on users, as opposed to >> unit tests which are just a convenience for you, the developer). >> >> I have more (I wrote a bit of that in my book) but heading out for now. >> >> -- >> Cédric >> >> >> -- >> Cédric >> >> >> >> On Fri, Feb 21, 2014 at 1:08 PM, Rakesh <rakesh.m...@gmail.com> wrote: >> >>> Hi, >>> >>> **usual disclaimer about not looking to start a flame war** >>> >>> A friend of mine recently interviewed at a company for a position as an >>> iOS dev. >>> >>> The topic of TDD came up and my friend stated that she was a big fan. >>> >>> The interviewer on the other hand, said he wasn't and that the 'jury was >>> still out'. >>> >>> I'm curious, who is the 'jury'? >>> >>> As for myself, if i can join a team doing tdd or be in a position where >>> i can, i'm happy. >>> >>> This group is stocked with experienced devs so i'm not looking to >>> convert anyone, but surely by now, the nay sayers are in the decline? >>> >>> Thoughts? >>> >>> Rakesh >>> >>> Ps kevin, REALLY interested in your opinion. >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Java Posse" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to javaposse+...@googlegroups.com. >>> To post to this group, send email to java...@googlegroups.com. >>> Visit this group at http://groups.google.com/group/javaposse. >>> For more options, visit https://groups.google.com/groups/opt_out. >>> >> >> -- You received this message because you are subscribed to the Google Groups "Java Posse" group. 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