trouble testing named routes

Hi there,
wondering if anyone could help me here.
I'm trying to test some named routes with the following:

def test_route
    opts = { :controller => "artists", :action => "list" }
    assert_routing "/admin/artists", opts
    # as per http://www.robsanheim.com/2006/07/22/testing-named-routes-or-url_for-in-functional-test/
    get :list url = get general_artist_url # this is line 51 which breaks
    assert_equal "/admin/artists", url
...
end

I have a route (which I know already works...):

  map.with_options :controller => 'artists' do |a|
    a.general_artist 'admin/artists/:action', :requirements => { :action => /create|list|new|destroy/ }, :defaults => { :action => 'list' }
    a.named_artist 'admin/artists/:animate_artist/:action', :requirements => { :action => /edit|update|show|preview/ }
    a.artist_form 'admin/artists/:animate_artist/:action/:id', :action => 'list'
    # add other options here if necessary later
  end

and I get:

  1) Error:
test_routes(ArtistsControllerTest):
ActionController::UnknownAction: No action responded to http://test.host/admin/artists
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:368:in `perform_action_without_benchmark'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/benchmarking.rb:69:in `perform_action_without_rescue'
    /opt/local/lib/ruby/1.8/benchmark.rb:293:in `measure'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/benchmarking.rb:69:in `perform_action_without_rescue'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/rescue.rb:82:in `perform_action'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/base.rb:381:in `send'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/base.rb:381:in `process_without_filters'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/filters.rb:377:in `process_without_session_management_support'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/session_management.rb:117:in `process_without_test'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/test_process.rb:16:in `process'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/test_process.rb:363:in `process'
    /Users/dorian/Sites/animate/rails/config/../vendor/rails/actionpack/lib/action_controller/test_process.rb:336:in `get'
    functional/artists_controller_test.rb:51:in `test_routes'

I'm not sure what this test.host is. I'm testing locally on my mac laptop. My assert_routing is all working fine, but I would like to test named_routes so that I can be sure they work when I use _url or url_for in my app.

anyone have any ideas what might be happening here?

thanks

dorian