Loss of opaque names for simple types

Description

I am trying to wrap a primitive type such as a string with an opaqueWrapper. This is correctly rendered using swagger, but OpenAPI 'sees through' the wrapper and the underlying primitive type appears in the method signatures of the resulting generated code.

openapi-generator version

current master

OpenAPI declaration file content or url

definitions:
  request:
    type: object
    required:
      - opaque
    properties:
      opaque:
        $ref: '#/definitions/opaqueWrapper'

opaqueWrapper:
  type : string
  description: A string in an opaque format.

Command line used for generation

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