Recover files that were git added, but never committed before a git-reset

recovery.rb

#!/usr/bin/env ruby

hours_ago = ARGV.shift
recovery_dir = ARGV.shift

Dir.mkdir(recovery_dir) unless File.exists?(recovery_dir)

# find all objects that were created less than X hours ago
files = `find .git/objects -type f -atime -#{hours_ago}h`.split("\n")

files.each do |filename|
  # this is how git will refer to the object
  object_hash = filename.split('/')[-2,2].join('')

  # skip meta-objects
  next unless object_hash =~ /^[0-9a-f]+$/

  # skip non-blob objects; commit messages, etc
  next unless `git cat-file -t #{object_hash}` =~ /blob/

  # save blob; sorry, the names of the files themselves are not recoverable
  `git cat-file -p #{object_hash} > #{recovery_dir}/#{object_hash}`
end

After this begins the fun of grepping through possibly hundreds of files looking for your lost, scared snippet of uncommitted code. I'm rooting for you!