Initializer is inaccessable due to 'internal' protection level
Just add to your FacebookLoginStrategy:
public init() {}As long as you do not implement init() explicitly, it is marked as internal by default. You need to overwrite that permission level to be able to instantiate from outside your framework.
If you are running in to this in code within an XCTestCase, make sure that you have added @testable import My-Awesome-App to the top of your test file.