Input for OpenAPI Generator bug https://github.com/OpenAPITools/openapi-generator/issues/9289

swagger.json

{
  "swagger": "2.0",
  "info": {
    "title": "Test swagger",
    "version": "0.1.0"
  },
  "definitions": {
    "File": {
      "title": "File",
      "type": "object",
      "properties": {
        "name": {
          "type": "string"
        }
      }
    },
    "Folder": {
      "title": "Folder",
      "type": "object",
      "properties": {
        "files": {
          "type": "array",
          "items": {
            "$ref": "#/definitions/File"
          }
        }
      }
    }
  },
  "paths": {},
  "host": "localhost:3000",
  "schemes": ["http"]
}