What's needed to implement polymorphism support for dart?

[allComputableThings]

I've been using -g dart for a project. Now, I'm adding a polymorphic property to an object, and finding that the dart generator doesn't support it. -g dart-dio does, however that would require changes throughout my project (because the modelled objects have no regular constructor, and are not mutable).

So... possible to add polymorphism to -g dart? How much work does that look like it might be? Where would I start?

[dbanty]

You're probably looking for https://github.com/OpenAPITools/openapi-generator