I’m a big fan of automated unit testing. I don’t always develop test-first, but I do always try to make sure I end up with a good set of tests for whatever code I’m writing. For JavaScript (in the browser), I’ve settled on QUnit as my unit testing framework of choice. It’s easy to use and works well.

Ideally, you’ll have tests that cover every part of the code. For some projects, it’s pretty easy to tell when this is the case. But if you find yourself writing tests for a complex piece of code that didn’t have many (or any) tests beforehand, as I did recently, then it can be good to know exactly how much of the code is being tested, and which bits still need to be exercised through tests. This is where a code coverage tool comes in. Continue reading →

Sometimes when you’re programming (or working on any project, really) you’ll discover some feature or issue that requires a lot of work to do properly. It’s often something that you completely overlooked during your initial design work, a tricky bug that came up during testing, or a use case that only some users will find.

A few months ago I made a simple Rubik’s Cube page and put it up on the web. More recently, I discovered it had a bug; a pretty serious bug that meant it wasn’t doing at all what it was supposed to be doing, namely simulating an actual Rubik’s Cube. Fixing it was hard. It meant rethinking the entire design of my code. I spent more time fixing this bug than I did on the entire first version of the project. At the moment I’m wrestling with a similar issue on my current project. To make it work well in 100% of all possible use cases is taking considerably longer than it took to make it work 80% right. Programming projects are full of these types of issues that look simple until you start working on them and realise they’re not. Continue reading →

I’ve worked in a number of different software development teams, and some of the best have been when I’ve been part of a team of 3 people. In this post I discuss some of the features of such teams, what helps them work well, what can harm them and my subjective experiences of working on such teams. I can’t say categorically that 3 is the optimum team size. Clearly, the right size of team is going to depend on many things. But if you happen to be on a team of 3, or you work with one, this might be helpful.

Teams of 3 Are Self-Organising

A long time ago, in a book I’ve long since forgotten, there was a diagram about team size and the number of communication channels required to keep each member informed. It looked something like this:

As the number of team members goes up, the number of communication channels increases exponentially.

Continue reading →

Your code has bugs in it. Here are some ways you can find them.

Test It Yourself

I do two things to test the code I write before anyone else sees it. First, I tend to write automated unit tests as I go along, in a kind of test-driven development style. These don’t so much find bugs as prevent them from occurring in the first place, as they force me to think about the requirements the code must fulfil before I write it. They are probably at their most useful though when you discover a bug through other types of testing. Then you can use a new unit test to reproduce the bug, fix it, and be confident that it will stay fixed through future versions of the code. Continue reading →

Recently I was working on a tricky problem. It was one of those problems that only occurs on a test server but not on a development box. Since the test server was hosted on Azure (the same as our live server), this made it really tricky to debug. Doing a manual deployment to the test server takes about 40 minutes. So my write-test-debug cycle was about an hour! To make things worse, it was an intermittent problem, so I could never be 100% sure when it was going to occur. And to make things even worse, I discovered that the only way to reliably get the problem to occur was to do another deployment. Simply stopping and restarting the server, which would have been much quicker, didn’t have the same effect. Yet another complicating factor was that the error that occurred wasn’t in our own code, but instead it seemed to be in some other code that was executing when a page was loaded, before our code ran. So the call stack in the exception was a load of functions in the .NET framework that I couldn’t get at.

All of this meant that I had to treat this like a science experiment: Get as much info out of the system as possible, with some hacked in debug logging, to try and find out where the problem was occurring. And try various things to see if I could get the problem to occur consistently and (eventually) to make the problem go away consistently. This involved a lot of deploying of slightly different versions of the code! Continue reading →

I was having a conversation recently with someone and we got onto the topic of how someone who’s smart and good at building things in software isn’t necessarily good at making or fixing hardware (by which I mean anything physical, including home improvements etc). I’m one of these people. It seems like many of the skills should be the same: the ability to visualise the desired end result, putting smaller pieces together to make the whole, the curiosity and intelligence to figure out how things work, the patience and concentration required to complete the job. But they are still different skills and both require different types of practice to get good at them.

Generally I believe that anyone can learn any skill if they’re prepared to practice. However there are many aspects of working with real physical things that I just plain don’t like and, when compared to software, annoy me too much. So I’ve never really been motivated to practice and get good at them. Continue reading →

While I’m reasonably skilled at working with HTML and CSS code, I’m a hopeless graphic designer. I have tried to make nice looking websites in the past, but they always end up looking ugly. My attempts at minimalism come out boring, and my attempts at exciting look busy and confusing. And besides, I’d rather work on code than design anyway.

So I make use of the many available web templates from sites like ThemeForest. These always look amazing in their demos on the site, and I can usually find something that suits whatever project I’m working on. But it’s not quite so simple when I come to work with these templates for my site. Continue reading →