[Enhancement] Add support for MapSets

[kerryb]

It looks like Hammox doesn’t currently support typespecs that use MapSet.t, because these use Elixir’s :sets module internally, and that declares its types as records.

I’ve created a trivial project to demonstrate the issue – I’m not sure I’ve got the skills to figure out how to fix it, but I might give it a try if I get time.

[brettbeatty]

Just ran into this same problem. Looks like the underlying type for MapSet now is :sets.set/1, which is a union of both old version (record) and new (map). So even though MapSet will always have the map version the typespec includes a record version.