XmlFile:test.xml
  PsiElement(XML_DOCUMENT)
    PsiElement(XML_PROLOG)
      PsiElement(XML_DOCTYPE)
        XmlToken:XML_DOCTYPE_START('<!DOCTYPE')
        PsiWhiteSpace(' ')
        XmlToken:XML_NAME('x3')
        PsiWhiteSpace(' ')
        PsiElement(XML_MARKUP_DECL)
          XmlToken:XML_MARKUP_START('[')
          PsiElement(XML_NOTATION_DECL)
            XmlToken:XML_NOTATION_DECL_START('<!NOTATION')
            PsiWhiteSpace(' ')
            XmlToken:XML_NAME('data-sources')
            PsiWhiteSpace(' ')
            XmlToken:XML_DOCTYPE_SYSTEM('SYSTEM')
            PsiWhiteSpace(' ')
            PsiElement(XML_ATTRIBUTE_VALUE)
              XmlToken:XML_ATTRIBUTE_VALUE_START_DELIMITER('"')
              XmlToken:XML_ATTRIBUTE_VALUE_TOKEN('x3')
              XmlToken:XML_ATTRIBUTE_VALUE_END_DELIMITER('"')
            XmlToken:XML_TAG_END('>')
          XmlToken:XML_MARKUP_END(']')
        XmlToken:XML_DOCTYPE_END('>')
    XmlTag:
      PsiErrorElement:Valid XML document must have a root tag
        <empty list>