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• Have you validated the input using an OpenAPI validator?
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Description

When generating Protobuf schemas for composed schemas that contain nested structures with enum references, the codegen incorrectly treats enums in maps and arrays as primitive string types, resulting in StringMap and StringArray wrappers instead of the correct enum-typed wrappers.

spec:

components:
  schemas:
    Fruit:
      type: string
      enum:
        - APPLE
        - BANANA
        - ORANGE
    
    FruitByColor:
      type: object
      additionalProperties:
        $ref: '#/components/schemas/Fruit'
    
    FruitList:
      type: array
      items:
        $ref: '#/components/schemas/Fruit'
    
    FruitInventory:
      oneOf:
        - title: fruitList
          $ref: '#/components/schemas/FruitList'
        - title: fruitColor
          $ref: '#/components/schemas/FruitByColor'

protobuf:

enum Fruit {
  FRUIT_APPLE = 0;
  FRUIT_BANANA = 1;
  FRUIT_ORANGE = 2;
}
message FruitInventory {

  oneof fruit_inventory {

    StringArray fruit_list = 1;

    StringMap fruit_color = 2;

  }
}

• A map containing enum values → should generate named enum map type (e.g., FruitMap)
• An array containing enum items → should generate named enum array type (e.g., FruitArray)

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