So how does the Grumpy Programmer write code, TDD style? It starts with using a set of tools that reduce the amount of friction required.
First, I do almost all my work from a terminal. On my Macbook I use iTerm 2 instead of the stock Terminal.app. Until recently you could not get 256 colours without some external hacking and since I like my editor to have purty colours I needed a terminal to match it. I might take a look at Terminal.app again, but iTerm 2 fits the bill.
Why the terminal? PHPUnit is a CLI application. Yes, many popular editors and IDE’s can do things like execute PHPUnit for you, but they are limited in what flexibility they provide. At Kaplan we have several different configurations under which we can run our tests. Again, reduce the friction between the tools and you using them.
Here’s what I use:
- Pathogen to make loading other plugins easy
- DiffDir for making code review and test reviews easier
- surround.vim - it has ruined me for using other editors
- tagbar - INDISPENSABLE
There is nothing specific to doing TDD in these plugins, but what they do for me is allow me to slice and dice text as quickly as possible, along with providing me with easy ways to navigate through the code base. Remember, reducing friction is a big thing to me. If the tool makes it tough for me to do what I want, it will be the target of grumpy ranting.
One of the reasons I like Sublime Text 2 is that you can jump all over the place in the code base in similar ways. If you editor doesn’t allow you to do that, you need to get rid of that editor and use something that does. NO EXCUSES.
A typical coding session has me using two terminal windows. One has Vim running in it, the other is used to run PHPUnit or other testing framework of choice as I venture in the world of BDD and testing in other languages. Then I do the following:
- figure out HOW to test the code I’m writing
- write the tests required
- write code until the tests pass
- refactor code as required
- refactor tests as required.
That’s really all their is to it. The actual work flow of when you are using TDD isn’t magical. I will admit that experience is the only teacher for how to actually write the tests, but luckily I have an awesome co-worker who bellows obscenities at me while guiding me down the path to total testing mastery. I know Will, you only hate me because you love me.
Every time I make a change to a test or the code, I re-run the tests. I find that this lets me get more done while actually slowing down the pace. You end up more focussed on the bit of code that really needs your attention, instead of getting drawn into blind alleys.
I also frequently run code-coverage reports to make sure that I’m getting maximum coverage for my efforts, while ignoring writing tests specifically for methods with very low CRAP indexes. Again, I’m making sure that I am targeting the parts of my code that need to be tested.
I know I’ve written about this before, but when you approach things from a TDD perspective, you find that using things like dependency injection become second nature.
If there is a lesson to be learned from this, it’s to make sure that every tool that you use reduces the friction that is generated when building your application using TDD.