find unused date formats

unused_date_format_finder.rb

a = "apache
batch_name
datetime_with_seconds
download_csv_datetime
download_csv_timezone
expiration
mmdd
mmyy
hhmmss
iso8601_milliseconds
receipt
short_date
short_date_dialog
short_datetime
time_with_seconds
short_military
long_date
time_with_zone
transparent_redirect
yymmdd
adyen_event_date
date_hour_minute_second_millis "

b = a.split("\n").map {|i| i.strip}

c = b.map {|format|
  app_res = `grep -Rin ".to_s(:#{format}" app`
  spec_res = `grep -Rin ".to_s(:#{format}" spec`
  res = app_res + "\n" + spec_res
  puts res
  [format, res]
}

d = c.select{|format, res|
  (res == "" || res == "\n")
}.map { |format, res|
  format
}

puts "unused formats: #{d}"
# unused formats: ["apache", "expiration", "mmyy", "short_military", "time_with_zone"]