How to wirte BDD and Unit tests for Electron.js Applications?

I am new to Electron and couldn't figure out how to write test(Unit and BDD) for Electron Applications. I am using Angular as the framework.

The main question is how exactly we can test somethings like the native OS functionalities like the Notifications or Dialog boxes to name a few.

If you guys have any good reads with you, please do share them.

Thanks in Advance.