use_rails in andrewroth_activeadmin-0.3.4.4

- old
+ new

@@ -1,10 +1,12 @@
 #!/usr/bin/env ruby
 #
 # Switches the development environment to use the given
 # version of rails. Caches the Gemfile.locks so that 
 # switching it very fast.
+#
+require File.expand_path("../../spec/support/detect_rails_version", __FILE__)
 
 def cmd(command)
   puts command
   exit 1 unless system command
 end
@@ -32,15 +34,20 @@
 # --clobber passed in
 if File.exists?(gem_lock_file) && ARGV.include?('--clobber')
   cmd "rm #{gem_lock_file}"
 end
 
-unless File.exists?(gem_lock_file)
-  # Generate it
+write_rails_version(version)
+
+# Ensure that bundler installs
+ENV['RUBYOPT'] = ''
+
+if File.exists?(gem_lock_file)
+  cmd("rm Gemfile.lock") if file_or_symlink?("Gemfile.lock")
+  cmd("ln -s #{gem_lock_file} Gemfile.lock")
+  cmd("bundle")
+else
   cmd "rm Gemfile.lock" if file_or_symlink?("Gemfile.lock")
-  cmd "export RAILS=#{version} && bundle install"
+  cmd "bundle install"
   cmd "mv Gemfile.lock #{gem_lock_file}"
+  cmd("ln -s #{gem_lock_file} Gemfile.lock")
 end
-
-cmd("rm Gemfile.lock") if file_or_symlink?("Gemfile.lock")
-cmd("ln -s #{gem_lock_file} Gemfile.lock")
-cmd("bundle")