Revert r42938 "* lib/rubygems: Update to RubyGems 2.1.3"

It breaks build.
http://u64.rubyci.org/~chkbuild/ruby-trunk/log/20130913T200302Z.diff.html.gz

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42941 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 17 insertions, 9 deletions

diff --git a/lib/rubygems/gem_runner.rb b/lib/rubygems/gem_runner.rb
index 8060e15312..7a3fd6b116 100644
--- a/lib/rubygems/gem_runner.rb
+++ b/lib/rubygems/gem_runner.rb
@@ -33,17 +33,11 @@ class Gem::GemRunner
   ##
   # Run the gem command with the following arguments.
 
-  def run(args)
-    if args.include?('--')
-      # We need to preserve the original ARGV to use for passing gem options
-      # to source gems.  If there is a -- in the line, strip all options after
-      # it...its for the source building process.
-      # TODO use slice!
-      build_args = args[args.index("--") + 1...args.length]
-      args = args[0...args.index("--")]
-    end
+  def run args
+    build_args = extract_build_args args
 
     do_configuration args
+
     cmd = @command_manager_class.instance
 
     cmd.command_names.each do |command_name|
@@ -60,6 +54,20 @@ class Gem::GemRunner
     cmd.run Gem.configuration.args, build_args
   end
 
+  ##
+  # Separates the build arguments (those following <code>--</code>) from the
+  # other arguments in the list.
+
+  def extract_build_args args # :nodoc:
+    return [] unless offset = args.index('--')
+
+    build_args = args.slice!(offset...args.length)
+
+    build_args.shift
+
+    build_args
+  end
+
   private
 
   def do_configuration(args)