Testing without a testing framework

I have been doing a lot of Unit Testing in my day job using NUnit as the framework. I find writing code to test code is very interesting and makes my coding efforts less bug prone. However in my off time I often mess around with non .Net programming projects and I miss the ability to write test code in these projects. Well it is not too hard to follow the same sort of unit testing practices when you do not have a testing framework in place.

Just recently I was writing some BX24 code for a robotic project. I needed to create some conversion procedures to go from a Byte/Integer to a String and a String to a Byte/Integer. How would I determine that my new procedures would work as designed? Certainly I could not rely on the production robot code to test the conversion procedure.

The BX24 programming language has the concept of projects and source modules. A project is nothing more than a collection of source modules. One of the source modules must be the main entry point of the project for starting execution. This concept allows me to simply create test projects that are designed to test a single source module.

So I moved my conversion procedures into a Conversion Module and made a Conversion Test project. Then I proceeded to write test code in the main module of the Conversion Test project to exercise the Conversion Module. I now had unit tests that exercised the outer bounds of the Conversion Module. I proceeded to fix bugs in the Conversion Module until all tests passed.

Of course without a framework I did not have the nice GUI with Red/Green lights to tell me a test passed or failed but it sure did help me determine if my module was fully functional or not. So if you have a programming project that does not have a nice unit testing harness but your IDE supports module level programming you to can use the above techniques to write bug free code.