TextMate command to copy a GitHub URL for selected code to clipboard

gistfile1.rb

#!/usr/bin/env ruby

filename = ENV['TM_FILEPATH']
root_dir = ENV['TM_DIRECTORY']
root_dir = File.dirname(root_dir) until File.directory?("#{root_dir}/.git") or root_dir == "/"
Dir.chdir root_dir

file_path = filename.sub("#{root_dir}/", '')

if ENV['TM_INPUT_START_LINE']
  start_line = ENV['TM_INPUT_START_LINE'].to_i
  end_line = start_line + ENV['TM_SELECTED_TEXT'].rstrip.scan("\n").size
  range = start_line..end_line
else
  line = ENV['TM_LINE_NUMBER'].to_i
  range = line..line
end

branch = `git symbolic-ref HEAD`.chomp.sub('refs/heads/', '')
remote_name = `git config branch.#{branch}.remote`.chomp

if remote_name.empty?
  remote_name = 'origin'
  remote_branch = branch
else
  remote_branch = `git config branch.#{branch}.merge`.chomp.sub('refs/heads/', '')
end

remote_url = `git config remote.#{remote_name}.url`.chomp.sub(/\.git$/, '')

rev = `git rev-parse #{remote_name}/#{remote_branch}`[0, 7]
range_out = if range.begin == range.end
  range.begin
else
  "#{range.begin}-#{range.end}"
end

remote_url =~ %r{github\.com[/:]([^/]+)/([^/]+)}

url = "http://github.com/#{$1}/#{$2}/blob/#{rev}/#{file_path}#L#{range_out}"

IO.popen('pbcopy', 'w') { |cp| cp << url }
puts url