git recent branches

#!/usr/bin/env ruby -wKU
# encoding: UTF-8

# prints out the last 15 git branches you used

reflog = IO.popen('git reflog')
$branches = []

def add_branch(b)
  $branches << b unless $branches.include? b
end

all_branches = IO.popen('git branch').readlines.map { |x| x.gsub('* ', '').strip }

reflog.readlines.each do |line|
  if line.match(/moving from (\S+) to (\S+)/)
    add_branch($1) if all_branches.include? $1
    add_branch($2) if all_branches.include? $2
  end

  break if $branches.size > 15
end

puts "* #{$branches[0]}"
$branches.drop(1).each { |b| puts b }