Ruby if block refactor from new synthax needed
Guidelines Rubocop

The guidelines favor if/case over multi-line ternary operator when a line is too long.


  
  Maximum Line Length   Limit lines to 80 characters.
  No Multi-line Ternary   Avoid multi-line ?: (the ternary operator); use if/unless instead.
  Use if/case Returns   Leverage the fact that if and case are expressions which return a result.
  


Refactored Code

def show
  identification_document = IdentificationDocument.find(params[:id])
  authorize identification_document
  return unless identification_document

  document =
    if params[:size] == 'resized'
       identification_document.id_document_resized
    else
       identification_document.id_document
    end

  send_data(document.file.read, filename: identification_document.file_name)
end