[Swift] Inheritance issue

Created by: SergeyPetrachkov

Description

Hi guys, I've installed the latest generator via homebrew and now I'm trying to generate a client for my iOS app. I appreciate structs over classes (Apple does too!), but here is one problem with inheritance, as Swift structs being value types do not support inheritance. There's a base class and a few descendants described in API yaml. Descendants do not inherit base's properties and I get invalid API client.

openapi-generator version

3.3.4 (latest available with Homebrew

OpenAPI declaration file content or url

here is a gist

Sorry, I can't provide the full spec

Command line used for generation

openapi-generator generate -l swift4 -i XXX

Suggest a fix/enhancement

I would think of either generating abstract descendants as classes or use a composition pattern and stay with structs. Though I am not sure either is easily possible