Testing platforms

[jonathanKingston]

@princiya asked how we should be testing the extension so lets discuss that here.

This example has both functional and unit tests: https://github.com/Standard8/example-webextension

Unit tests likely make the most sense for the storage methods. For browser apis we potentially could mock them but I suspect it might make more sense to make those functional tests.

I don't think there needs to be a rush to decide right now which libraries are best.
Personally for unit testing I have used mocha and chai assert a lot. I also have used ava which seems very promise ready: https://github.com/avajs/ava

[jonathanKingston]

@princiya the code https://github.com/electrolyfish/lightbeam-we/blob/master/js/store.js#L62 needs to be moved into non functional code, even if we make it require a console call to trigger it for now. However moving this to be a test would be neater.