I just committed basic unit testing support to Renquist, implemented using Python's unittest framework. The results were quite pleasing. Now I can quickly run multiple automated tests to ensure correct behavior and avoid regressions! Huzzah!
For my first two tests I decided to try using a blank file as both a Feed and as a List. The blank Feed test uncovered a bug I hadn't considered, while the blank List test made me fix a problem I had already tagged as a failure point in the comments of the source code. Both bugs are fixed now, but there's surely still a lot of code that isn't being touched by these tests. But how can I identify those untested lines of code?
The first thing I thought after writing those two test cases was, "There should be a way to visually identify the untested code." After looking through the Python documentation, the first thing I found was the "trace" module, which can output every single line that gets run. It would take almost no work at all to generate a very simple HTML file, highlighting tested code (or untested code).
Before I write that software, though, I'm going to search a little online. I can't imagine that someone else hasn't had that idea, too.
Here's to automated testing!