How can I unit test a GUI?

Question

The calculations in my code are well-tested, but because there is so much GUI code, my overall code coverage is lower than I\'d like. Are there any guidelines on unit-testin

Answer 1

What I gather from your question is that you're looking for an automated way to test your GUI behavior in detail, the example you give is testing whether a curve is actually drawn correctly.

Unit testing frameworks provide a way to do automated testing, but I think the kind of tests you want to do are complicated integration tests that verify the correct behavior of a multitude of classes, among which the classes of your GUI toolkit/library, which you should not want to test.

Your options depend very much on what platforms/toolkits/frameworks you use: for example, an application using Qt as its GUI framework can use Squish to automate its tests. You verify the results of your tests once, and subsequent automatically executed tests compare results against the verified results.

Answer 2

You can use JFCUnit to test your GUI, but graphics can be more challenging. I have on a couple of occasions taken snapshots of my GUI and automatically compared it to a previous version. While this doesn't provide an actual test, it does alert you if an automatic build fails to produce the expected output.