Load path file from single location only

[virtuald]

• /home/lvuser/py/deploy/pathplanner/*.path on RoboRIO
• __main__ / deploy/pathplanner/*.path in simulation

[TheTripleV]

Will paths relative to robot.py still work? We've been using relative paths for all of our extra files (pathplanner and pathweaver before it).

[virtuald]

The path is relative to dirname(__main__.__file__), which should generally work. I'll try it on a roborio later tonight, but there's no reason it shouldn't work AFAIK.

[virtuald]

Confirmed on RoboRIO that this approach tries to load from /home/lvuser/py/deploy/pathplanner/*.path

[virtuald]

Will depend on robotpy/robotpy-wpilib#710 once merged.

[TheTripleV]

Paths relative to robot.py don't work with this PR.
A sample from our code::

self.scheduler.schedule(commands.autonomous.DriveTrajectory(self, './paths/5Ball1', 2, 3, False))

./paths/5Ball1 resolved before but doesn't now.

I get that pathplannerlib originally looked in a specific folder, but everywhere else in robot code, relative paths are relative to robot.py and it would be confusing to deviate from that.

[virtuald]

When you specify a robot 'project' in pathplanner, by default puts the files in the specific folder as you mention. It seems confusing to force users to have to copy the pathplanner files (as presumably your team does?). Additionally, the API specifies loading by name, not by a path, so this is staying with the original intent of the API.

With all that said, I agree that it would make sense to be able to load from any arbitrary location also, so maybe let's add another function that does that? Not sure what the right name would be though... loadFile?

[TheTripleV]

It's weird because here, the Path in loadPath refers to a trajectory but it generally refers to a PathLike. I'm fine with loadFile. Alternatively, would loadPath trying both be bad?