Script to delete old git branches

code.rb

require 'time'

branches = `git for-each-ref --format '%(refname:short) %(committerdate)' refs/heads/`

months_ago = 12
threshold = Time.now - (months_ago * 30 * 24 * 60 * 60)

branches_to_delete = {}

branches.each_line do |line|
  branch, last_commit_date_str = line.split(" ", 2)
  last_commit_date = Time.parse(last_commit_date_str.strip)

  if last_commit_date < threshold
    branches_to_delete[branch] = threshold
  end
end

unless branches_to_delete.any?
  puts "did not find any branches to delete!"
  exit
end

puts "Last updated\tbranch"
branches_to_delete.each do |branch,date|
  print date
  print "\t"
  puts branch
end

puts "The above branches will be force-deleted. Hit enter to continue, control-c to cancel."
gets

branches_to_delete.each do |branch, _|
  system("git branch -D #{branch}")
end