File arrays are broken for multipart forms

[nigredo-tori]

Q&A (please complete the following information)

• OS: Ubuntu 18.10
• Browser: Chrome
• Version: 74.0.3729.169
• Method of installation: dist asset link (unpkg.com)
• Swagger-UI version:
• Swagger/OpenAPI version: OpenAPI 3.0.2

Content & configuration

Example Swagger/OpenAPI definition:

openapi: 3.0.2
info:
  title: foo
  version: "0.1"
servers:
  - url: http://localhost:4444
paths:
  /test:
    post:
      requestBody:
        content:
          multipart/form-data:
            schema:
              type: object
              properties:
                foo:
                  type: array
                  items:
                    type: string
                    format: binary
      responses:
        '200':
          description: baz

Swagger-UI configuration options:

SwaggerUIBundle({
  url: "openapi.yaml",
  dom_id: '#swagger-ui',
  deepLinking: true,
  presets: [
    SwaggerUIBundle.presets.apis,
    SwaggerUIStandalonePreset
  ],
  plugins: [
    SwaggerUIBundle.plugins.DownloadUrl,
    HideTopbarPlugin
  ],
  layout: "StandaloneLayout",
})

Describe the bug you're encountering

A multipart property defined like this:

foo:
   type: array
   items:
     type: string
     format: binary

To reproduce...

Steps to reproduce the behavior:

1. Go to https://editor.swagger.io .
2. Paste the OpenAPI config from above.
3. Start capturing the request via Wireshark (loopback, port 4444 - as defined in the config).
4. Open the POST test tab.
5. Press "Try it out".
6. Add a few files to the array.
7. Press "Execute".
8. See in the Wireshark that the request looks like the example above.

Expected behavior

Produced multipart request should have one part per file in array, containing the data from the corresponding file.

Additional context or thoughts

File arrays are described here.

[nigredo-tori]

Nevermind, this is a duplicate of #4600