Allow Erlang to download from GitHub.

Erland has an official GitHub repository. Cloning this repository is
faster than downloading the official tarball, so we (ab)use head to
allow for this alternate download:
    brew install erlang --HEAD

Fixes #1179.

1 files changed, 11 insertions, 5 deletions

diff --git a/Library/Formula/erlang.rb b/Library/Formula/erlang.rb
index 7de5fba05..d8a2d0b33 100644
--- a/Library/Formula/erlang.rb
+++ b/Library/Formula/erlang.rb
@@ -9,6 +9,9 @@ class Erlang <Formula
   version 'R13B04'
   url "http://erlang.org/download/otp_src_#{version}.tar.gz"
   md5 'ca6da4921e438891967900aa6a084341'
+
+  # Use `brew install erlang --HEAD` to download from (faster than tarball) GitHub repo.
+  head "git://github.com/erlang/otp.git", :tag => "OTP_R13B04"
   homepage 'http://www.erlang.org'
 
   # we can't strip the beam executables or any plugins
@@ -24,12 +27,15 @@ class Erlang <Formula
     ENV.deparallelize
     ENV.gcc_4_2 # see http://github.com/mxcl/homebrew/issues/#issue/120
 
+    # If building from GitHub, this step is required (but not for tarball downloads.)
+    system "./otp_build autoconf" if File.exist? "otp_build"
+
     config_flags = ["--disable-debug",
-                          "--prefix=#{prefix}",
-                          "--enable-kernel-poll",
-                          "--enable-threads",
-                          "--enable-dynamic-ssl-lib",
-                          "--enable-smp-support"]
+                    "--prefix=#{prefix}",
+                    "--enable-kernel-poll",
+                    "--enable-threads",
+                    "--enable-dynamic-ssl-lib",
+                    "--enable-smp-support"]
 
     unless ARGV.include? '--disable-hipe'
       # HIPE doesn't strike me as that reliable on OS X