git.rb

##
# Returns the command that will check out +revision+ from the
# repository into directory +destination+.  +revision+ can be any
# SHA1 or equivalent (e.g. branch, tag, etc...)

def checkout(revision, destination)
  destination = File.join(destination, 'repo')
  revision = 'HEAD' if revision =~ /head/i

  [ "rm -rf #{destination}",
    "#{git_cmd} clone #{repository} #{destination}",
    "cd #{destination}",
    "#{git_cmd} checkout -f -b deployed-#{revision} #{revision}",
    "cd -"
  ].join(" && ")
end