This is a library designed to emulate parts of WPILib (we have not implemented all of it, since we didn't need it) so you can more easily do unit testing of your robot code on any platform that supports python3, without having to have a cRio around for testing. Our team used it last year with our robot code, this is a better packaged version of that same code.
In particular, we use this to quickly run our robot code in all modes before uploading it to the robot, to ensure that there aren't any obvious indentation or syntax errors that might not have been caught otherwise. An example that does this is included, called 'import_test'
Please let us know if you use it, and how we can make it better -- and submit patches to add/fix functionality! We will be updating it as we use it.
Probably during the regular season this will be released in a separate package on the RobotPy website. For now, you can download it via the RobotPy github site at
https://github.com/robotpy/fake-wpilib
One thing that we have implemented with it is a pyTkinter-based game for our students to code against -- using this library and a GUI implementation, they can drive their robot code around on a virtual field shown on the screen. We're planning on implementing objects and stuff on the field and interactive sensors and stuff, so that they can learn robot programming even easier without a robot. We have not yet released this code, but probably in the future when it's more complete.