go: added --use-git-head option to formula.

Uses http://github.com/tav/go.git git mirror of official Mercurial
repository to obviate the need for installing Mercurial.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

1 files changed, 15 insertions, 1 deletions

diff --git a/Library/Formula/go.rb b/Library/Formula/go.rb
index 361e7d28b..c7bfdfcd3 100644
--- a/Library/Formula/go.rb
+++ b/Library/Formula/go.rb
@@ -2,9 +2,19 @@ require 'formula'
 require 'hardware'
 
 class Go <Formula
-  head 'http://go.googlecode.com/hg/', :revision => 'release'
+  if ARGV.include? "--use-git-head"
+    head 'http://github.com/tav/go.git', :revision => 'release'
+  else
+    head 'http://go.googlecode.com/hg/', :revision => 'release'
+  end
   homepage 'http://golang.org'
 
+  def options
+    [
+     ["--use-git-head", "Use git mirror instead of official hg repository"],
+    ]
+  end
+
   skip_clean 'bin'
 
   def which_arch
@@ -35,6 +45,10 @@ class Go <Formula
 
   def caveats
     <<-EOS.undent
+      The official Go code repository uses mercurial, but a reasonably 
+      up-to-date git mirror is available at http://github.com/tav/go.git.
+      To use the git mirror for Go builds, use the --use-git-head option.
+
       In order to use Go, set the following in your ~/.profile:
 
         export GOROOT=`brew --cellar go`