strange link_to behavior on links to controllers in modules

Hey Amol,

The relevant code is in /actionpack/lib/action_controller/routing.rb on line 348:

      # Returns a controller path for a new +controller+ based on a +previous+ controller path.
      # Handles 4 scenarios:
      #
      # * stay in the previous controller:
      #     controller_relative_to( nil, "groups/discussion" ) # => "groups/discussion"
      #
      # * stay in the previous namespace:
      #     controller_relative_to( "posts", "groups/discussion" ) # => "groups/posts"
      #
      # * forced move to the root namespace:
      #     controller_relative_to( "/posts", "groups/discussion" ) # => "posts"
      #
      # * previous namespace is root:
      #     controller_relative_to( "posts", "anything_with_no_slashes" ) # =>"posts"
      #
      def controller_relative_to(controller, previous)
        if controller.nil?           then previous
        elsif controller[0] == ?/    then controller[1..-1]
        elsif %r{^(.*)/} =~ previous then "#{$1}/#{controller}"
        else controller
        end
      end
    end

From that, it looks the current behaviour is intended. Perhaps bring up a discussion on the mailing list?

Also, just by the bye, your test fails for me, but not for the reason you describe. The first link_to call just generates "http://example.com", rather than a route at all. (That's on the latest edge rails).