Tuesday, April 28, 2009

twitter is cool...

So if you haven't figured out twitter I'll try and help...

Twitter is technically a "micro blogging service"... but that does not really do it justice.

To describe twitter simply, it would go something like this. Twitter is a mechanism for people to distribute short pieces of text (140 chars) to people who have elected to be on their list.

Text communiques are known as "tweets" and people who receive them are "followers".

So then, what is the big deal?

The key difference is that for me to follow someone I do not require their permission. Unlike facebook where in order to receive status updates from people both sides need to agree.

So I could therefore follow Oprah Winfrey or Ashton Kutcher, or even Hugh Jackman.

So if you want to know what your hero is doing/thinking/wanting to tell the world... then why don't you look them up on twitter and follow them. You'll not only know what they're thinking about what you're interested in, you'll also probably know when they come back from a cycle.

Oh and btw, you can find me on twitter.

Thursday, April 16, 2009

Unit Testing, what do I need to get it right?

So you want to do Unit Testing... it's a noble goal and good goal that every development shop or environment should have.

And it is a goal that we had at the beginning of our project.

It didn't happen, or certainly not as I would have liked.

So then, what did I learn from our so called failure, what are the mandatory requirements for making unit testing a sucess...
  1. Infrastructure to automatically run unit tests. In order to make unit testing work, you must have some facility to run the unit tests regularly. Preferably these should run fast and should be run on every checkin. It is not enough to rely on the developer to run the unit tests before they checkin their changes.
  2. A univeral commitment to quality. Your whole development team needs to be fully and categorically commited to quality, and a working unit testing system is a necessary requirement to get there. For a unit testing system to work it means that if tests fail, developers need to care - as soon as one unit test fails, your system is immediately less effective. The unit test frameworks do not work when even one test is failing. You can't have just one developer, say the lead developer, telling developers to fix their unit tests.
  3. Mangement buy in. The problem we had with unit tests and getting unit tests fixed is that developers always made some excuse about how they could fix it now, they just had this bug to fix or this use case to finish, so management need to realise that a reason for the use case being delayed is because I had unit tests to fix is as good a reason as, there was a power failure and I couldn't use my PC.
The benefits of unit tests are proven, but I can't prove those benefits to you, here. You have to do it, 100%, pay the cost - and it's true, there is a cost, but the pay off from paying that price worth it, you'll probably gain 3 times as much you put in. But don't bother, unless you've ticked the 3 boxes outlined above.

Tuesday, April 14, 2009

Commit comments... more is more

First off I must say that it has been a long time since I last posted - I have just been swamped with work on www.sanlamconnect.co.za.

The other day the issue of what is a good commit comment came up... and there are a number of approaches to this issue.

The big question is, Should it stand alone? IOW should it make sense by itself, or should it be taken in conjunction with diff. If you apply the former then the comment will repeat what the developer can ascertain from the diff and typically add more information. If you apply the latter then the developer is required to look at the diff to make sense of what is going on.

So the other day a fellow developer accused me of being too terse in my commit comment, and I was a little indignant at his criticism because I regarded my commit comments as being adequate. I felt why must I rehash what the user can see from the diff. The comment as far as I remember was "fixing bug"...

I reasoned, if the user has any sense they can look at the diff and they can figure out what the bug was and what I did to fix it.

But would it have killed me to just put down maybe another 10 words to indicate more details, like "fixed bug in execute target, the file extension was placed incorrectly". Is that too much to ask? Another 10 words that would have taken me another second to write that is going to save the next person at least the time it takes to open the diff, notwithstanding the time it's going to take them to make sense of it.

So, the conclusion is, write detailed commit comments. Definitely a paragraph is not necessary, but at least 10 words is a good start.

What about those developers that would have taken another minute to write those 10 words because they can't touch type... to them I say, tough, it's time you learnt.




Wednesday, April 08, 2009

The Double Importance of Unit Testing when more than one developer is involved

So now, you have a team of 10 developers working on a project, I know it's a lot, but some projects have that number...

And so a solution is required to a problem and both developers require a solution to the problem. For any number of reasons, both developers end up solving the problem, not in exactly the same way mind you.

The result is that you have two solutions to the same problem.

Now what? You have 2 options...

1. You could leave the code as it is. This is surprisingly enough, a viable option, since it's done often enough! But it's clearly not ideal as it leaves you with duplicate code and duplicate functionality. And if you consistently apply this approach then before long you'll have many many instances where this occurs. Maybe inside that duplicate code there is another facility that is required and thus duplicated. And if you consider that with 10 developers involved, you can have many many instances where developers are unfamiliar with what other developers have done, so you have exponentially more instances where functionality is duplicated. The more developers you have, the more duplication. Each time a developer is added, the potential for duplication is exponentially higher based on the number of connections. With 2 developers, only 1 piece of communication is requried per piece of work, with 3, 2 pieces etc... each time you add another developer, the probability of duplication is significantly increased. So you inevitable end up with multiple ways of solving the same problem with code that differs in its quality (different developers wrote each one)

2. You could however, refactor, such that both parties use the same functionality. A more appropriate solution; but easier said than done right? It sounds good in theory but it is not practiced. Why not? What if it doesn't work? What if there was one little consideration the one version used and depended on that the other version didn't have or do? Then the implementations are not exactly the same and thus cannot simply be amalgamated. How do I know the implementation that now depends on new code is going to work. Unless you have some facility to validate the changed process you don't really know. You could of course start up the application and exercise the functionality from both points of view to validate they both work. A clunky and time consuming process that will hold you back from making the change in the first place. That's where unit tests come in.

Unit tests let you remove duplication and refactor with confidence allowing you to improve quality, conciseness, readability and delivery times.