class Date

def to_s(format = NOT_SET) # :nodoc:
  if formatter = DATE_FORMATS[format]
    ActiveSupport::Deprecation.warn(
      "Date#to_s(#{format.inspect}) is deprecated. Please use Date#to_fs(#{format.inspect}) instead."
    )
    if formatter.respond_to?(:call)
      formatter.call(self).to_s
    else
      strftime(formatter)
    end
  elsif format == NOT_SET
    to_default_s
  else
    ActiveSupport::Deprecation.warn(
      "Date#to_s(#{format.inspect}) is deprecated. Please use Date#to_fs(#{format.inspect}) instead."
    )
    to_default_s
  end
end