ERC777 change visibility of some attributes and methods from private to internal

🧐 Motivation I’m trying to extend the base ERC777 contract to be pauseable, but ran into an issue. The best way I can think of to accomplish this is to override _move(), _mint() and _burn() to check if the contract is paused, but _move()'s visibility is private, so it can’t be overridden. I’d also like to create setter methods for _name and _symbol but can’t because they are private also.

📝 Details I’m wondering what the rationale is for making methods/attributes private and if it’s okay to change some of them to internal, namely move(), _name and _symbol. I’ll submit a pull request if there are no objections.

[frangio]

a scenario where a function is pausable without us realizing it because it indirectly moves tokens around.

Wouldn’t this be desirable though? I would expect that if I pause the contract all moving is paused.

I still don’t think exposing _move is a good idea anyway.

My proposal is to make the ERC777 interface functions public rather than external as they are now. This allows people to override them to add functionality and to create new external functions that make use of them.

[frangio]

Hi @JonahGroendal! Your use case sounds quite reasonable!

Unfortunately though, we do have a strict policy of keeping all variables private.

Rather than forking, I would highly encourage you to inherit the contract, create the 2 extra variables, and add overrides. I agree that it sounds messy, but it’s more aligned with the recommended way to use the library. It’s highly discouraged to fork and modify the code for yourself because you can accidentally introduce bugs, and even though this particular case is harmless, when it comes to security conventions it’s better to strictly follow them always.

Similarly to the private variables, I think _move is too low-level a function for us to safely expose internally. Unfortunately you won’t be able to modify send and transfer through overrides either because they’re external and super.send will not compile. This is a shortcoming of our current implementation that we should fix. We closed things down as much as possible initially to keep our options open, to see what features users would need and what would be the best interface we can provide for them. Apologies that you ran into these issues!

@nventuro what do you think we should do here to enable the implementation of a Pausable ERC777?