desc "Bundle all Gemfiles"
task :bundle do |_t, opts|
  ["Gemfile", *Dir.glob("gemfiles/*.gemfile")].each do |gemfile|
    Bundler.with_original_env do
      system({ "BUNDLE_GEMFILE" => gemfile }, "bundle", *opts)
    end
  end
end

desc "Bundle all Gemfiles"
task :bundle do |_t, opts|
  ["Gemfile", *Dir.glob("gemfiles/*.gemfile")].each do |gemfile|
    Bundler.with_original_env do
      system({ "BUNDLE_GEMFILE" => gemfile }, "bundle", opts)
    end
  end
end

--- 
+++ 
@@ -2,7 +2,7 @@
 task :bundle do |_t, opts|
   ["Gemfile", *Dir.glob("gemfiles/*.gemfile")].each do |gemfile|
     Bundler.with_original_env do
-      system({ "BUNDLE_GEMFILE" => gemfile }, "bundle", opts)
+      system({ "BUNDLE_GEMFILE" => gemfile }, "bundle", *opts)
     end
   end
 end
Fix error in the `rake bundle` task

So that `bundle exec rake bundle[update,loofah]` works.
