homebrew mxcl master sync script for github fork in default remote AKA origin

upgrade_forked_brew.sh

#!/usr/bin/env zsh

# Sync mxcl homebrew with a forked version
#
# Usage: upgrade_forked_brew.sh && git push origin

emulate -L zsh

local FORK_GITHUB_USER=martialboniou

github_urls(){
  g="github.com"
  a=(git://$g/$1/$2.git git@$g:$1/$2.git https://$g/$1/$2.git)
  print $a
}

test_remote_array() {
  declare -a rmts
  eval "rmts=( $1 )" && [ ${#rmts[*]} -ne 0 ] || ( echo "malformed array" && exit )
  rmt=$(git remote -v &> /dev/null | grep "^origin" | head -1 | awk '{print $2}')
  for i in $rmts; do
    [ "$rmt" = "$i" ] && return 0
  done
  return 1
}

enable_remote_for() {
  declare -a a
  s=$(github_urls $1 $2)
  # create new origin if different
  test_remote_array $s || ( a=( ${=s} ) && git remote add origin $a[1] )
}

() {
  cd `brew --prefix` &&
  () {
    declare -a mxcls_url
    # check origin
    enable_remote_for "$FORK_GITHUB_USER" "homebrew"
    mxcls=$(github_urls "mxcl" "homebrew")
    mxcl_urls=( ${=mxcls} ) && local mxcl_url=$mxcl_urls[1] || exit
    # create a mxcl if none
    (git ls-remote --heads $mxcl_url &> /dev/null || git remote add mxcl $mxcl_url) \
      && git checkout master 2> /dev/null \
      && git pull mxcl master
  }
}