In computer programming, unit testing is a software testing method by which individual units of source code, sets of one or more computer program modules together with associated control data, usage procedures, and operating procedures, are tested to determine whether they are fit for use.
Wikipedia
Most languages have a unit testing library and Xojo is no exception. Not surprisingly, the Xojo unit testing library is called XojoUnit. It is available for free on GitHub:
https://github.com/xojo/XojoUnit
XojoUnit can be used with Desktop, Console, Web and iOS projects. We use XojoUnit ourselves to run unit tests on the Xojo framework as part of our continuous integration build process.
Watch this quick video to see how you can quickly incorporate XojoUnit into your own projects: