enum default value changes when defined in referenced file

The default value of an enum changes depending on whether it is defined in the main input file or in a referenced file.
Although I'm new to swagger-parser, this seems like a bug to me. Using the flatten and resolveFully options doesn't make a difference.

Example 1

input1.yaml:

openapi: 3.0.3
info:
  version: 1.0.0
  title: Issue Demo
  description: none

paths:
  /test:
    $ref: 'input1Child.yaml#/paths/~1test'

input1Child.yaml:

components:
  parameters:
    pets:
      name: pets
      in: query
      schema:
        type: array
        items:
          $ref: '#/components/schemas/Pet'
        default: [DOG, FISH]

  schemas:
    Pet:
      type: string
      enum:
        - DOG
        - CAT
        - FISH

paths:
  /test:
    get:
      description: Returns ad for a given ad ID.
      operationId: getAd
      parameters:
        - $ref: '#/components/parameters/pets'
      responses:
        '200':
          description: OK
          content:
            text/plain:
              schema:
                type: string
                example: pong```

Here the pets default value is parsed to be [DOG, FISH].

Example 2

input2.yaml:

openapi: 3.0.3
info:
  version: 1.0.0
  title: Issue Demo
  description: none

components:
  parameters:
    pets:
      name: pets
      in: query
      schema:
        type: array
        items:
          $ref: '#/components/schemas/Pet'
        default: [DOG, FISH]

  schemas:
    Pet:
      type: string
      enum:
        - DOG
        - CAT
        - FISH

paths:
  /test:
    get:
      description: Returns ad for a given ad ID.
      operationId: getAd
      parameters:
        - $ref: '#/components/parameters/pets'
      responses:
        '200':
          description: OK
          content:
            text/plain:
              schema:
                type: string
                example: pong

Here the pets default value is parsed to be ["DOG","FISH"].

I used the latest swagger-parser version, 2.1.16, for these examples. And I created a minimal executable example at https://github.com/martin-mfg/swagger-parser-demo that demos the issue.

Start by running the minimal executable example linked in the issue and compare input1.yaml with input2.yaml, focusing on how the referenced input1Child.yaml is resolved. Trace the parser's reference-resolution and default-value handling, then verify that both examples produce the same default representation.