Resources: url_for([parent, child]) generates /parents/1/children/2 for the nested resource. Likewise with the other simply helpful methods like form_for and link_to. Closes #6432.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6951 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

6 files changed, 174 insertions, 45 deletions

diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index e155be9d46..3f77234d03 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Resources: url_for([parent, child]) generates /parents/1/children/2 for the nested resource. Likewise with the other simply helpful methods like form_for and link_to.  #6432 [mhw, Jonathan Vaught]
+
 * Assume html format when rendering partials in RJS. #8076 [Rick]
 
 * Don't double-escape url_for in views.  #8144 [Rich Collins, Josh Peek]
diff --git a/actionpack/lib/action_controller/polymorphic_routes.rb b/actionpack/lib/action_controller/polymorphic_routes.rb
index c60b533205..6c21bc27c5 100644
--- a/actionpack/lib/action_controller/polymorphic_routes.rb
+++ b/actionpack/lib/action_controller/polymorphic_routes.rb
@@ -1,31 +1,29 @@
 module ActionController
   module PolymorphicRoutes
-    def polymorphic_url(record_or_hash, options = {})
-      record = extract_record(record_or_hash)
-
-      case
-      when options[:action] == "new"
-        send(
-          action_prefix(options) + RecordIdentifier.singular_class_name(record) + routing_type(options)
-        )
-
-      when record.respond_to?(:new_record?) && record.new_record?
-        send(
-          action_prefix(options) + RecordIdentifier.plural_class_name(record) + routing_type(options)
-        )
-
-      else
-        send(
-          action_prefix(options) + RecordIdentifier.singular_class_name(record) + routing_type(options), record_or_hash
-        )
-      end
+    def polymorphic_url(record_or_hash_or_array, options = {})
+      record = extract_record(record_or_hash_or_array)
+
+      args = []
+      inflection =
+        case
+        when options[:action] == "new"
+          :singular
+        when record.respond_to?(:new_record?) && record.new_record?
+          :plural
+        else
+          args = [record_or_hash_or_array]
+          :singular
+        end
+
+      named_route = build_named_route_call(record_or_hash_or_array, inflection, options)
+      send(named_route, *args)
     end
 
-    def polymorphic_path(record_or_hash)
-      polymorphic_url(record_or_hash, :routing_type => :path)
+    def polymorphic_path(record_or_hash_or_array)
+      polymorphic_url(record_or_hash_or_array, :routing_type => :path)
     end
 
-    %w( edit new formatted ).each do |action|
+    %w(edit new formatted).each do |action|
       module_eval <<-EOT, __FILE__, __LINE__
         def #{action}_polymorphic_url(record_or_hash)
           polymorphic_url(record_or_hash, :action => "#{action}")
@@ -44,11 +42,27 @@ module ActionController
       end
 
       def routing_type(options)
-        "_#{options[:routing_type] || "url"}"
+        "#{options[:routing_type] || "url"}"
+      end
+
+      def build_named_route_call(records, inflection, options = {})
+        records = Array.new([extract_record(records)]) unless records.is_a?(Array)
+        base_segment = "#{RecordIdentifier.send("#{inflection}_class_name", records.pop)}_"
+
+        method_root = records.reverse.inject(base_segment) do |string, name|
+          segment = "#{RecordIdentifier.send("singular_class_name", name)}_"
+          segment << string
+        end
+
+        action_prefix(options) + method_root + routing_type(options)
       end
 
-      def extract_record(record_or_hash)
-        record_or_hash.is_a?(Hash) ? record_or_hash[:id] : record_or_hash
+      def extract_record(record_or_hash_or_array)
+        case record_or_hash_or_array
+          when Array: record_or_hash_or_array.last
+          when Hash:  record_or_hash_or_array[:id]
+          else        record_or_hash_or_array
+        end
       end
   end
 end
diff --git a/actionpack/lib/action_controller/record_identifier.rb b/actionpack/lib/action_controller/record_identifier.rb
index 1a60becff3..bdf2753a79 100644
--- a/actionpack/lib/action_controller/record_identifier.rb
+++ b/actionpack/lib/action_controller/record_identifier.rb
@@ -25,7 +25,7 @@ module ActionController
   #     end
   #   end
   #
-  # As the example above shows, you can stop caring to a large extend what the actual id of the post is. You just know
+  # As the example above shows, you can stop caring to a large extent what the actual id of the post is. You just know
   # that one is being assigned and that the subsequent calls in redirect_to and the RJS expect that same naming 
   # convention and allows you to write less code if you follow it.
   module RecordIdentifier
diff --git a/actionpack/lib/action_view/helpers/form_helper.rb b/actionpack/lib/action_view/helpers/form_helper.rb
index 7325aad398..1a4aa0ca05 100644
--- a/actionpack/lib/action_view/helpers/form_helper.rb
+++ b/actionpack/lib/action_view/helpers/form_helper.rb
@@ -163,9 +163,14 @@ module ActionView
         case record_or_name
         when String, Symbol
           object_name = record_or_name
+        when Array
+          object = record_or_name.last
+          object_name = ActionController::RecordIdentifier.singular_class_name(object)
+          apply_form_for_options!(object, options, *record_or_name)
+          args.unshift object
         else
-          object      = record_or_name
-          object_name = ActionController::RecordIdentifier.singular_class_name(record_or_name)
+          object = record_or_name
+          object_name = ActionController::RecordIdentifier.singular_class_name(object)
           apply_form_for_options!(object, options)
           args.unshift object
         end
@@ -174,18 +179,18 @@ module ActionView
         fields_for(object_name, *(args << options), &proc)
         concat('</form>', proc.binding)
       end
-      
-      def apply_form_for_options!(object, options) #:nodoc:
-        html_options = if object.respond_to?(:new_record?) && object.new_record?
-          { :class  => dom_class(object, :new),  :id => dom_id(object), :method => :post }
-        else
-          { :class  => dom_class(object, :edit), :id => dom_id(object, :edit), :method => :put }
-        end
-        
+
+      def apply_form_for_options!(object, options, *nested_objects) #:nodoc:
+        html_options =
+          if object.respond_to?(:new_record?) && object.new_record?
+            { :class  => dom_class(object, :new),  :id => dom_id(object), :method => :post }
+          else
+            { :class  => dom_class(object, :edit), :id => dom_id(object, :edit), :method => :put }
+          end
+
         options[:html] ||= {}
         options[:html].reverse_merge!(html_options)
-
-        options[:url] ||= polymorphic_path(object)
+        options[:url] ||= polymorphic_path(object, *nested_objects)
       end
 
       # Creates a scope around a specific model object like form_for, but doesn't create the form tags themselves. This makes
diff --git a/actionpack/test/template/form_helper_test.rb b/actionpack/test/template/form_helper_test.rb
index c9e7aeaeb3..c504190960 100644
--- a/actionpack/test/template/form_helper_test.rb
+++ b/actionpack/test/template/form_helper_test.rb
@@ -15,8 +15,21 @@ silence_warnings do
       @new_record
     end
   end
+
+  class Comment
+    attr_reader :id
+    attr_reader :post_id
+    def save; @id = 1; @post_id = 1 end
+    def new_record?; @id.nil? end
+    def name
+      @id.nil? ? 'new comment' : "comment ##{@id}"
+    end
+  end
 end
 
+class Comment::Nested < Comment; end
+
+
 class FormHelperTest < Test::Unit::TestCase
   include ActionView::Helpers::FormHelper
   include ActionView::Helpers::FormTagHelper
@@ -28,6 +41,7 @@ class FormHelperTest < Test::Unit::TestCase
 
   def setup
     @post = Post.new
+    @comment = Comment.new
     def @post.errors() 
       Class.new{ 
         def on(field); "can't be empty" if field == "author_name"; end 
@@ -579,6 +593,25 @@ class FormHelperTest < Test::Unit::TestCase
     assert_equal expected, _erbout
   end
 
+  def test_form_for_with_existing_object_in_list
+    @post.new_record = false
+    @comment.save
+    _erbout = ''
+    form_for([@post, @comment]) {}
+
+    expected = %(<form action="#{comment_path(@post, @comment)}" class="edit_comment" id="edit_comment_1" method="post"><div style="margin:0;padding:0"><input name="_method" type="hidden" value="put" /></div></form>)
+    assert_dom_equal expected, _erbout
+  end
+
+  def test_form_for_with_new_object_in_list
+    @post.new_record = false
+    _erbout = ''
+    form_for([@post, @comment]) {}
+
+    expected = %(<form action="#{comments_path(@post)}" class="new_comment" id="new_comment" method="post"></form>)
+    assert_dom_equal expected, _erbout
+  end
+
   def test_form_for_with_existing_object_and_custom_url
     _erbout = ''
 
@@ -600,11 +633,27 @@ class FormHelperTest < Test::Unit::TestCase
 
 
   protected
-    def polymorphic_path(record)
-      if record.new_record?
-        "/posts"
+    def comments_path(post)
+      "/posts/#{post.id}/comments"
+    end
+
+    def comment_path(post, comment)
+      "/posts/#{post.id}/comments/#{comment.id}"
+    end
+
+    def polymorphic_path(object, *nested_objects)
+      if nested_objects.empty?
+        if object.new_record?
+          "/posts"
+        else
+          "/posts/#{object.id}"
+        end
       else
-        "/posts/#{record.id}"
+        if object.new_record?
+          "/posts/123/comments"
+        else
+          "/posts/123/comments/#{object.id}"
+        end
       end
     end
 end
diff --git a/actionpack/test/template/url_helper_test.rb b/actionpack/test/template/url_helper_test.rb
index 43ec8ca0d3..1a5521b3e4 100644
--- a/actionpack/test/template/url_helper_test.rb
+++ b/actionpack/test/template/url_helper_test.rb
@@ -375,6 +375,22 @@ class Workshop
   end
 end
 
+class Session
+  attr_accessor :id, :workshop_id, :new_record
+
+  def initialize(id, new_record)
+    @id, @new_record = id, new_record
+  end
+
+  def new_record?
+    @new_record
+  end
+
+  def to_s
+    id.to_s
+  end
+end
+
 class PolymorphicControllerTest < Test::Unit::TestCase
   class WorkshopsController < ActionController::Base
     self.view_paths = ["#{File.dirname(__FILE__)}/../fixtures/"]
@@ -394,15 +410,36 @@ class PolymorphicControllerTest < Test::Unit::TestCase
     def rescue_action(e) raise e end
   end
 
+  class SessionsController < ActionController::Base
+    self.view_paths = ["#{File.dirname(__FILE__)}/../fixtures/"]
+
+    def self.controller_path; 'sessions' end
+
+    def index
+      @workshop = Workshop.new(params[:workshop_id], false)
+      @session = Session.new(1, true)
+      render :inline => "<%= url_for([@workshop, @session]) %>\n<%= link_to('Session', [@workshop, @session]) %>"
+    end
+
+    def show
+      @workshop = Workshop.new(params[:workshop_id], false)
+      @session = Session.new(params[:id], false)
+      render :inline => "<%= url_for([@workshop, @session]) %>\n<%= link_to('Session', [@workshop, @session]) %>"
+    end
+
+    def rescue_action(e) raise e end
+  end
+
   include ActionView::Helpers::UrlHelper
 
   def setup
     @request    = ActionController::TestRequest.new
     @response   = ActionController::TestResponse.new
-    @controller = WorkshopsController.new
   end
 
   def test_new_resource
+    @controller = WorkshopsController.new
+
     with_restful_routing do
       get :index
       assert_equal "/workshops\n<a href=\"/workshops\">Workshop</a>", @response.body
@@ -410,19 +447,41 @@ class PolymorphicControllerTest < Test::Unit::TestCase
   end
 
   def test_existing_resource
+    @controller = WorkshopsController.new
+
     with_restful_routing do
       get :show, :id => 1
       assert_equal "/workshops/1\n<a href=\"/workshops/1\">Workshop</a>", @response.body
     end
   end
 
+  def test_new_nested_resource
+    @controller = SessionsController.new
+
+    with_restful_routing do
+      get :index, :workshop_id => 1
+      assert_equal "/workshops/1/sessions\n<a href=\"/workshops/1/sessions\">Session</a>", @response.body
+    end
+  end
+
+  def test_existing_nested_resource
+    @controller = SessionsController.new
+
+    with_restful_routing do
+      get :show, :workshop_id => 1, :id => 1
+      assert_equal "/workshops/1/sessions/1\n<a href=\"/workshops/1/sessions/1\">Session</a>", @response.body
+    end
+  end
+
   protected
     def with_restful_routing
       with_routing do |set|
         set.draw do |map|
-          map.resources :workshops
+          map.resources :workshops do |w|
+            w.resources :sessions
+          end
         end
         yield
       end
     end
-end
\ No newline at end of file
+end