class Thor::Group

def handle_argument_error(task, error, arity=nil) #:nodoc:
  if arity > 0
    msg = "#{basename} #{task.name} takes #{arity} argument"
    msg << "s" if arity > 1
    msg << ", but it should not."
  else
    msg = "You should not pass arguments to #{basename} #{task.name}."
  end
  raise error, msg
end