I recently finished reading the Art of Unit Testing, by Roy Osherove (Manning); here are a few thoughts on the book.

Who to give it too

This is an excellent book for the C# developer with solid foundations in object-oriented design, who has already some exposure to writing unit tests. If you have worked on a decent-scale project, and found yourself thinking “hmmm, I am sure there is a smarter way to write these tests”, you should definitely get that book. Note that while it will be extremely useful to the test-driven development practitioner, this is NOT a book on TDD.More...

Much ado on the interwebs has followed Joel’s recent post on the now-infamous Duct Tape Programmer. You have to give it to Joel, he has a talent for writing pieces which get lots of people really worked up – what in some circles is called trolling. Out of curiosity, I looked up Google Trends, and unless some other piece of hot news related to duct tape surfaced on Sept 23rd, you can see with your naked eye the amount of buzz this one single post managed to generate. Impressive.

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Silicon Valley Code Camp version 4.0 took place this week-end, and was a big success, judging by the numbers and the happy faces. Congratulations to Peter Kellner and the team for a tremendous organization!

Personally, I wanted to give a big thank-you to the people who attended my session on Test-Driven Development – and for bearing with my voice, which was pretty shaky. I got sick this week and wasn’t sure until Saturday evening if I could do it, because on Thursday my voice was totally gone. I think I had more herbal tea with honey this week than in my entire life, but you guys made it all worth it: I had a great time giving my presentation, and you guys rocked!

As I said during the session, the theory behind TDD is pretty succinct, so there isn’t much in the slides themselves worth posting. Instead, I thought I would list a few pointers:

NUnit: you can find it here. I recommend checking out the Quick Start page, which covers most of what you need to start writing unit tests. I have written a post on data-driven tests here.

While we are talking about tools, I haven’t presented it during the session, but I really like TestDriven.Net. There is a free community version for your personal use. It’s a Visual Studio add-on which allows you to run and debug your tests from Visual Studio.

Even though it’s a Java book, and this session was for .NET developers, I really recommend Kent Beck’s book Test-Driven Development by Example. It’s very easy to read, and will get you started on the right foot. It’s also very well written – one of my favorite books!

The other book I recommend is the Art of Unit Testing, by Roy Osherove. I just finished it, and I wish I had it with me a few years ago, when I began writing tests seriously :) The book is technically about unit testing and not TDD, and it is a .NET book. I highly recommend it, it is chock-full of good advice, and covers way more than just testing.

That’s it! If you are interested in either the slides or code, let me know, and I’ll gladly post them, too. In the meanwhile, thanks again for coming, and… happy testing!

I had an Eureka moment today, and realized that I was trying hard to resolve the wrong problem, when what was needed was a change of frame.

I have been developing an application which tracks differences between Excel worksheets, and displays them in a layout similar to Excel itself. The user can navigate through the sheet on display by using two scrollbars, just like he would with Excel.

To achieve this, my approach so far has been to read the data, create a grid using WPF, adding one cell control to the grid for each cell in the spreadsheet, and navigate “over” that grid using the scroll bars.

This approach works well as long as the spreadsheet is small, but for larger sheets – say, 200 x 200 cells - the time needed to create the cells and add them to the grid was getting pretty long, so I focused my attention on figuring out a way to populate the grid faster, without much success.

Then yesterday, someone wrote this on StackOverflow:

I'm going to go out on a limb here and say that trying to add 40,000 controls is your real bottleneck; not so much as to how you're adding the controls.

Indeed – that’s completely correct.This didn’t answer my issue directly, but it has been liberating, and got me to rethink the question from a different angle – do I really need 40,000 cells?

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It’s that time of the year again: Silicon Valley Code Camp is coming up on October 3rd and 4th, at Foothill College. If you live in the Bay Area and like to talk code, this is an event you don’t want to miss. The previous editions rocked, and this year looks like it’s going to rock even harder, with well over 100 sessions and close to 1,000 registered! Oh, and did I mention it’s free?

This year again, I will give an introduction to Test-Driven Development for .NET developers. It’s a topic which is dear to my heart; in his book on TDD, Kent Beck says that it “is a way of managing fear during programming”, and I have to say that my life as a developer got significantly more peaceful after reading it. I can’t guarantee that you will feel the same, but I’ll do my best to share the goods!

The session is targeted for beginners. My goal is to get you quick-started so that you are ready to use it when you leave the room. I will write some code live, to show the methodology in action, using only tools you can get for free. This year, I think I will focus mostly on NUnit and keep it to a minimum on the tools provided in Visual Studio, unless there is strong popular demand; hopefully this will give me enough time to squeeze in a few minutes on mocks. I also just ordered Roy Osherove’s “The Art of Unit Testing”, which looks very promising, and may push me to modify my plan a bit.

I hope to see you there – and if you have questions or suggestions, let me know in the comments section!