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• 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?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

Using the petstore.yaml sample file, the provided enum is not reflected in the Go generated files

 Pet:
  title: a Pet
  description: A pet for sale in the pet store
  type: object
  required:
    - name
    - photoUrls
  properties:
    id:
      type: integer
      format: int64
    category:
      $ref: '#/components/schemas/Category'
    name:
      type: string
      example: doggie
    photoUrls:
      type: array
      xml:
        name: photoUrl
        wrapped: true
      items:
        type: string
    tags:
      type: array
      xml:
        name: tag
        wrapped: true
      items:
        $ref: '#/components/schemas/Tag'
    status:
      type: string
      description: pet status in the store
      enum:
        - available
        - pending
        - sold

the Pet structure is generated this way:

// Pet A pet for sale in the pet store
type Pet struct {
Id *int64 json:"id,omitempty"
Category *Category json:"category,omitempty"
Name string json:"name"
PhotoUrls []string json:"photoUrls"
Tags *[]Tag json:"tags,omitempty"
// pet status in the store
Status *string json:"status,omitempty"
}

It implies to add manually files to reflect these enums, this decreases the interested of such generated files, hard to maintain

openapi-generator version

latest master version (does not work with previous versions as well to my knowledge)
commit 6c40192 (HEAD -> master, origin/master, origin/HEAD)
Date: Mon May 24 07:01:16 2021 +0200

OpenAPI declaration file content or url

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/test/resources/3_0/petstore.yaml

Generation Details

./run-in-docker.sh generate -i petstore.yaml -g go -o /gen/out/petstore --skip-validate-spec --package-name=ps -c config.yaml

config.yaml:

additionalProperties:
generateInterfaces: "true"
enumClassPrefix: "true"
isGoSubmodule: "true"

Steps to reproduce

generate the go files using the provided generation details and the petstore.yaml file

Related issues/PRs

This is related to this issue: #8937
but for the golang language

Suggest a fix

Instead of using a *string, generate a new dedicated type and set the possible values accordingly