:to => redirect() can take a String using 1.9-style interpolation or proc that takes the path parameters as a Hash

actionpack/lib/action_dispatch/routing/mapper.rb

@@ -132,13 +132,19 @@ module ActionDispatch
           map_method(:delete, *args, &block)
         end
 
-        def redirect(path, options = {})
+        def redirect(*args, &block)
+          options = args.last.is_a?(Hash) ? args.pop : {}
+
+          path = args.shift || block
+          path_proc = path.is_a?(Proc) ? path : proc {|params| path % params }
           status = options[:status] || 301
-          lambda { |env|
+
+          lambda do |env|
             req = Rack::Request.new(env)
-            url = req.scheme + '://' + req.host + path
+            params = path_proc.call(env["action_dispatch.request.path_parameters"])
+            url = req.scheme + '://' + req.host + params
             [status, {'Location' => url, 'Content-Type' => 'text/html'}, ['Moved Permanently']]
-          }
+          end
         end
 
         private

actionpack/test/dispatch/routing_test.rb

@@ -24,6 +24,9 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
 
       match 'account/login', :to => redirect("/login")
 
+      match 'account/modulo/:name', :to => redirect("/%{name}s")
+      match 'account/proc/:name', :to => redirect {|params| "/#{params[:name].pluralize}" }
+
       match 'openid/login', :via => [:get, :post], :to => "openid#login"
 
       controller(:global) do
@@ -145,6 +148,24 @@ class TestRoutingMapper < ActionDispatch::IntegrationTest
     end
   end
 
+  def test_redirect_modulo
+    with_test_routes do
+      get '/account/modulo/name'
+      assert_equal 301, @response.status
+      assert_equal 'http://www.example.com/names', @response.headers['Location']
+      assert_equal 'Moved Permanently', @response.body
+    end
+  end
+
+  def test_redirect_proc
+    with_test_routes do
+      get '/account/proc/person'
+      assert_equal 301, @response.status
+      assert_equal 'http://www.example.com/people', @response.headers['Location']
+      assert_equal 'Moved Permanently', @response.body
+    end
+  end
+
   def test_openid
     with_test_routes do
       get '/openid/login'

activesupport/lib/active_support/ruby/shim.rb

@@ -14,5 +14,6 @@ require 'active_support/core_ext/date_time/conversions'
 require 'active_support/core_ext/enumerable'
 require 'active_support/core_ext/process/daemon'
 require 'active_support/core_ext/string/conversions'
+require 'active_support/core_ext/string/interpolation'
 require 'active_support/core_ext/rexml'
 require 'active_support/core_ext/time/conversions'