XML Example can't be generated if last property is an attribute

[jweisman]

Given the below pet.yaml definition, when the favorite property of the Tag object is defined first, the XML example is generated correctly. When the favorite property is last, the following error is thrown:

javax.xml.stream.XMLStreamException: Trying to write an attribute when there is no open start element.
    at com.ctc.wstx.sw.BaseStreamWriter.throwOutputError(BaseStreamWriter.java:1584)
    at com.ctc.wstx.sw.BaseStreamWriter.reportNwfStructure(BaseStreamWriter.java:1613)
    at com.ctc.wstx.sw.BaseNsStreamWriter.writeAttribute(BaseNsStreamWriter.java:231)
    at io.swagger.oas.inflector.examples.XmlExampleSerializer.writeTo(XmlExampleSerializer.java:160)
    at io.swagger.oas.inflector.examples.XmlExampleSerializer.writeTo(XmlExampleSerializer.java:81)
    at io.swagger.oas.inflector.examples.XmlExampleSerializer.writeTo(XmlExampleSerializer.java:135)
    at io.swagger.oas.inflector.examples.XmlExampleSerializer.writeTo(XmlExampleSerializer.java:81)
    at io.swagger.oas.inflector.examples.XmlExampleSerializer.serialize(XmlExampleSerializer.java:39)
    at MakeSwaggerExamples.main(MakeSwaggerExamples.java:61)
Exception in thread "main" java.lang.NullPointerException
    at java.io.StringReader.<init>(StringReader.java:50)
    at MakeSwaggerExamples.main(MakeSwaggerExamples.java:67)

Pet:
  type: object
  required:
    - name
    - photoUrls
  properties:
    id:
      type: integer
      format: int64
    category:
      $ref: './category.yaml#/Category'
    name:
      type: string
      example: doggie
    photoUrls:
      type: array
      xml:
        name: photoUrl
        wrapped: true
      items:
        type: string
    tag:
      type: array
      xml:
        name: tags
        wrapped: true
      items:
        $ref: '#/Tag'
        xml:
          name: tag
    status:
      type: string
      description: pet status in the store
      enum:
        - available
        - pending
        - sold
  xml:
    name: Pet
Tag:
  type: object
  properties:
    favorite:
      type: boolean
      xml:
        attribute: true
    id:
      type: integer
      format: int64
    name:
      type: string
  xml:
    name: tag       

[gracekarina]

hi @jweisman which version of openapi are you using, if you can share the full spec will be great. thanks

[jweisman]

Hi @gracekarina - I'm using OpenAPI 3.0. The spec I shared here can reproduce the issue. Does it not reproduce for you? Thanks!