`ListInputType[T]` extending `InputType[Seq[T]]`

[keuhdall]

Hi, this is more of a question than an actual issue, but is there any reason as of why ListInputType[T] extends InputType[Seq[T]] while on the other hand, ListType[T] extends OutputType[Iterable[T]] ?
I think having them both as Iterable would be nice !

[yanns]

ListType[_] was changed quite recently for that: #904
I guess a similar change for ListInputType[_] would make sense.
Would you want to open a PR for this?

[keuhdall]

Sure, no problem, I'll try working on it this week !

[keuhdall]

So I just started working on it, unfortunately it might no be very straightforward, maybe I'm having the wrong approach here but it seems that we would also need an update of the sangria-marshalling-api repository, as we might be missing an implicit for creating Arguments, the apply method requires 3 implicit parameters:

toInput: ToInput[Default, _],
fromInput: FromInput[T],
res: ArgumentType[T]

But the trait FromInput has the following implementation:

class SeqFromInput[T](delegate: FromInput[T]) extends FromInput[Seq[T]]

I don't mind giving a try at changing all that to Iterable, but I guess that could be bothersome to release, as it would need to rely first on a new version the the marshalling api that has the new implicit. It would also probably be quite a lot of changes.
Once again I don't mind trying, that could an interesting first contribution, but I don't know what's your take on that, let me know !

[yanns]

Indeed, this could be a bit complex.
And I can spot some .asInstanceOf[Seq[Any]] in sangria-marshalling-api, meaning that we cannot rely on types to catch all issues here... 😭

If you have time / energy to go down the rabbit hole, I'll help you. For example, I can cut a beta release of sangria-marshalling-api with some changes of your if you want to test something. Otherwise you can publish locally, and use the snapshot version.

But if you don't have the time / energy, I'll understand perfectly.

[keuhdall]

I'll give it a try, but it might take me some time before coming out with something as there's quite a few projects I'm working on in parallel already, I'll give an update on whether I manage to deliver something or not here !