Add Arduino CI with GitHub Actions

[skallaher]

These changes include the use of the arduino_ci tool as well as a GitHub Action to run unit tests for Linux, MacOS, and Windows.

Running locally:

• Install Ruby and Bundler (gem install bundler)
• bundle install # adds packages to global library (may require admin rights)
• bundle install --path vendor/bundle # adds packages to local library
• bundle exec arduino_ci.rb

Notes:

• Due to this issue, python needs to be explicitly installed along with pyserial for the GitHub Action. This may also be necessary for your machine as well.
• Added empty barebones unittest for proof of concept. Actual tests needed, which will require a class that fakes the PAJ7620 sensor protocols.

[acrandal]

This is such great stuff.

[ianfixes]

I'd welcome any feedback you may have about where/how arduino_ci documentation should address the python dependency, either here or as a new issue. The next update to the action will be based on this PR and will include the python fix.

[skallaher]

@ianfixes, I mostly just read through the Readme file for the arduino_ci repo to get it running. This was overall a really smooth experience! If the Python dependency was mentioned around the You Need Ruby and Bundler and You Need A Compiler sections, that would be great. The only python package that I had to ensure was installed with pip is pyserial.

The only other speed bumps that I ran into when getting this running was Error during build: Error resolving FQBN: getting build properties for board esp8266:esp8266:huzzah: invalid option 'FlashSize'. This meant that I had to override the existing esp8266:esp8266:huzzah platform in the .arduino-ci.yml file to remove both FlashSize and CpuFrequency. I've not seen any other reports of this being a problem, so can't verify if it's just the contents of this repo which causes that to happen.

I did find the action repo after having implemented my own GitHub Action (this was my first foray into GitHub Actions, so I didn't think to look for it). If using this action is recommended, I didn't see mention of it in the README.md when implementing.

Thanks for reaching out! I found arduino_ci to be super quick and easy to get the basics setup and rolling!

[ianfixes]

Thanks, I've made that change to the README locally. I've also opened Arduino-CI/arduino_ci#254 -- thanks for making me aware of that.

The action is very new. On one hand, it's what I consider the future of the project to be -- it's easier for CI and doesn't involve troubleshooting a ruby installation. On the other hand, I'm still coordinating the documentation between the 2 projects. I think the README change that documents it hasn't been merged yet.

I will take a peek at adopting your python setup, since (if I'm understanding correctly) it actually works.