[BUG] Dart-dio serialization with discriminator

Description

So I'm trying to implement open api discriminator for serialization and deserialization but look like it doesn't work at all.

openapi-generator version

5.2.1

OpenAPI declaration file content

openapi: 3.0.3
info:
  title: KiWi API V1 Refined
  description: This is the refined version of Kiwi API
  contact:
    email: dev@kiwi-bop.com
  license:
    name: BSD License
  version: v1
paths:
  /api/v1/vehicules:
    post:
      requestBody:
        content:
          application/json:
            schema:
              discriminator:
                propertyName: powerSource
                mapping:
                  electricity: '#/components/schemas/ElectricVehicle'
                  gasoline: '#/components/schemas/FueledVehicle'
                  human-energy: '#/components/schemas/PedaledVehicle'
              anyOf:
                - $ref: '#/components/schemas/ElectricVehicle'
                - $ref: '#/components/schemas/FueledVehicle'
                - $ref: '#/components/schemas/PedaledVehicle'
      responses:
        '200':
          description: all good
          content:
            application/json:
              schema:
                type: array
                items:
                  discriminator:
                    propertyName: powerSource
                    mapping:
                      electricity: '#/components/schemas/ElectricVehicle'
                      gasoline: '#/components/schemas/FueledVehicle'
                      human-energy: '#/components/schemas/PedaledVehicle'
                  anyOf:
                    - $ref: '#/components/schemas/ElectricVehicle'
                    - $ref: '#/components/schemas/FueledVehicle'
                    - $ref: '#/components/schemas/PedaledVehicle'
components:
  schemas:
    Vehicle:
      type: object
      description: Vehicle
      discriminator:
        propertyName: powerSource
        mapping:
          electricity: '#/components/schemas/ElectricVehicle'
          gasoline: '#/components/schemas/FueledVehicle'
          human-energy: '#/components/schemas/PedaledVehicle'
      properties:
        vehicleType:
          description: The type of vehicle.
          type: string
          example: bicycle
        idealTerrain:
          type: string
          example: roads
        topSpeed:
          description: The top speed in kilometers per hour rounded to the nearest integer.
          type: integer
          example: 83
        powerSource:
          description: How is the vehicle powered.
          type: string
          example: pedaling
    FueledVehicle:
      allOf:
        - $ref: '#/components/schemas/Vehicle'
        - type: object
          title: Gas-powered Vehicle
          properties:
            range:
              description: The 95th percentile range of a trip in kilometers.
              type: integer
              example: 100
            tankCapacity:
              type: number
              format: double
              description: Capacity of the fuel tank in gallons.
            milesPerGallon:
              type: number
              format: double
              description: Miles per gallon on the highway.
    PedaledVehicle:
      allOf:
        - $ref: '#/components/schemas/Vehicle'
        - type: object
          description: Pedaled Vehicle
          properties:
            range:
              description: The 95th percentile range of a trip in kilometers.
              type: integer
              example: 100
    ElectricVehicle:
      allOf:
        - $ref: '#/components/schemas/Vehicle'
        - type: object
          description: Electric Vehicle
          properties:
            range:
              description: The 95th percentile range of a trip in kilometers.
              type: integer
              example: 100
            chargeSpeed:
              description: In range kilometers per hour.
              type: integer
            chargeAmps:
              description: Amps recommended for charging.
              type: integer
            chargeVoltage:
              description: Voltage recommended for charging.
              type: integer

Generation Details

It generates all kind of all_of weird models.

But also it doesn't compile at all in the end cause it tries to use non existing models:

lib/src/serializers.dart:36:45: Error: Undefined name 'AnyOfElectricVehicleFueledVehiclePedaledVehicle'.
        const FullType(BuiltList, [FullType(AnyOfElectricVehicleFueledVehiclePedaledVehicle)]),
                                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Is discriminator something supported by this generator? Not totally sure by the look of what is generated.

cc @josh-burton

Reproduce the Dart-dio generation from the supplied OpenAPI declaration and inspect the generated models plus lib/src/serializers.dart. Start with the serializer reference to AnyOfElectricVehicleFueledVehiclePedaledVehicle, then verify that generation produces existing model types and that the resulting client compiles with discriminator serialization and deserialization.