vendored_thor.rb in bundler-1.2.0.pre.1

- old
+ new

@@ -1,7 +1,8 @@
 if defined?(Thor)
   Bundler.ui.warn "Thor has already been required. " +
     "This may cause Bundler to malfunction in unexpected ways."
 end
-$:.unshift File.expand_path('../vendor', __FILE__)
+vendor = File.expand_path('../vendor', __FILE__)
+$:.unshift(vendor) unless $:.include?(vendor)
 require 'thor'
 require 'thor/actions'