[BUG] [cpp-qt-client] No support for AnyType objects

Created by: danielrenninghoff

Bug Report Checklist

Have you provided a full/minimal spec to reproduce the issue?
Have you validated the input using an OpenAPI validator (example)?
Have you tested with the latest master to confirm the issue still exists?
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Description

The cpp-qt-client generator produces invalid code (code that cannot be compiled) for AnyType objects.

...
#include "OAIAnyType.h"
...
QList<OAIAnyType> getArrayOfSomething() const;
...

The header OAIAnyType.h does not exist and is not generated and the type OAIAnyType is defined nowhere.

openapi-generator version

master - 6.0.0

OpenAPI declaration file content or url

Full scheme

arrayOfSomething:
          type: array
          items: {}
          nullable: true

Generation Details

Steps to reproduce

java -jar openapi-generator-cli.jar generate -i https://gist.githubusercontent.com/madrazzl3/da2502b6816aaa98713cba75e595f373/raw/d53da8c6098167768c3e5b1ad1381467397d6a51/example-scheme.yaml -g cpp-qt-client -o generated-client/

Related issues/PRs

Suggest a fix

Add type mapping AnyType -> QJsonValue. QJsonValue can be used to manually get the correct type later.