def fields(markdown)
      fields = []
      if markdown.file
        fields.push(title: 'file',
                    value: markdown.file,
                    short: true)
      end
      if markdown.line
        fields.push(title: 'line',
                    value: markdown.line,
                    short: true)
      end
      fields
    end
def fields(markdown)
      fields = []
      if markdown.file
        fields.push(title: 'file',
                    value: markdown.file,
                    short: true)
      end
      if markdown.line
        fields.push(title: 'line',
                    value: markdown.line,
                    short: true)
      end
      fields
    end
get markdown fields
 @return [[Hash]]