Changed API of NestedAttributes to take an array, or hash with index keys, of hashes that have the id on the inside of the attributes hash and updated the FormBuilder to produce such hashes. Also fixed NestedAttributes with composite ids.

Signed-off-by: Michael Koziarski <michael@koziarski.com>
Signed-off-by: Eloy Duran <eloy.de.enige@gmail.com>
[#1892 state:committed]

2 files changed, 48 insertions, 16 deletions

diff --git a/actionpack/lib/action_view/helpers/form_helper.rb b/actionpack/lib/action_view/helpers/form_helper.rb
index 3925978217..568687e9e0 100644
--- a/actionpack/lib/action_view/helpers/form_helper.rb
+++ b/actionpack/lib/action_view/helpers/form_helper.rb
@@ -964,24 +964,34 @@ module ActionView
         def fields_for_with_nested_attributes(association_name, args, block)
           name = "#{object_name}[#{association_name}_attributes]"
           association = @object.send(association_name)
+          explicit_object = args.first if args.first.respond_to?(:new_record?)
 
           if association.is_a?(Array)
-            children = args.first.respond_to?(:new_record?) ? [args.first] : association
+            children = explicit_object ? [explicit_object] : association
+            explicit_child_index = args.last[:child_index] if args.last.is_a?(Hash)
 
             children.map do |child|
-              child_name = "#{name}[#{ child.new_record? ? new_child_id : child.id }]"
-              @template.fields_for(child_name, child, *args, &block)
+              fields_for_nested_model("#{name}[#{explicit_child_index || nested_child_index}]", child, args, block)
             end.join
           else
-            object = args.first.respond_to?(:new_record?) ? args.first : association
+            fields_for_nested_model(name, explicit_object || association, args, block)
+          end
+        end
+
+        def fields_for_nested_model(name, object, args, block)
+          if object.new_record?
             @template.fields_for(name, object, *args, &block)
+          else
+            @template.fields_for(name, object, *args) do |builder|
+              @template.concat builder.hidden_field(:id)
+              block.call(builder)
+            end
           end
         end
 
-        def new_child_id
-          value = (@child_counter ||= 1)
-          @child_counter += 1
-          "new_#{value}"
+        def nested_child_index
+          @nested_child_index ||= -1
+          @nested_child_index += 1
         end
     end
   end
diff --git a/actionpack/test/template/form_helper_test.rb b/actionpack/test/template/form_helper_test.rb
index b7e4a933e1..5cc81b4afb 100644
--- a/actionpack/test/template/form_helper_test.rb
+++ b/actionpack/test/template/form_helper_test.rb
@@ -607,6 +607,7 @@ class FormHelperTest < ActionView::TestCase
 
     expected = '<form action="http://www.example.com" method="post">' +
                '<input name="post[title]" size="30" type="text" id="post_title" value="Hello World" />' +
+               '<input id="post_author_attributes_id" name="post[author_attributes][id]" type="hidden" value="321" />' +
                '<input id="post_author_attributes_name" name="post[author_attributes][name]" size="30" type="text" value="author #321" />' +
                '</form>'
 
@@ -627,8 +628,10 @@ class FormHelperTest < ActionView::TestCase
 
     expected = '<form action="http://www.example.com" method="post">' +
                '<input name="post[title]" size="30" type="text" id="post_title" value="Hello World" />' +
-               '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" size="30" type="text" value="comment #1" />' +
-               '<input id="post_comments_attributes_2_name" name="post[comments_attributes][2][name]" size="30" type="text" value="comment #2" />' +
+               '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="1" />' +
+               '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" size="30" type="text" value="comment #1" />' +
+               '<input id="post_comments_attributes_1_id" name="post[comments_attributes][1][id]" type="hidden" value="2" />' +
+               '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" size="30" type="text" value="comment #2" />' +
                '</form>'
 
     assert_dom_equal expected, output_buffer
@@ -648,8 +651,8 @@ class FormHelperTest < ActionView::TestCase
 
     expected = '<form action="http://www.example.com" method="post">' +
                '<input name="post[title]" size="30" type="text" id="post_title" value="Hello World" />' +
-               '<input id="post_comments_attributes_new_1_name" name="post[comments_attributes][new_1][name]" size="30" type="text" value="new comment" />' +
-               '<input id="post_comments_attributes_new_2_name" name="post[comments_attributes][new_2][name]" size="30" type="text" value="new comment" />' +
+               '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" size="30" type="text" value="new comment" />' +
+               '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" size="30" type="text" value="new comment" />' +
                '</form>'
 
     assert_dom_equal expected, output_buffer
@@ -669,8 +672,9 @@ class FormHelperTest < ActionView::TestCase
 
     expected = '<form action="http://www.example.com" method="post">' +
                '<input name="post[title]" size="30" type="text" id="post_title" value="Hello World" />' +
-               '<input id="post_comments_attributes_321_name" name="post[comments_attributes][321][name]" size="30" type="text" value="comment #321" />' +
-               '<input id="post_comments_attributes_new_1_name" name="post[comments_attributes][new_1][name]" size="30" type="text" value="new comment" />' +
+               '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' +
+               '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" size="30" type="text" value="comment #321" />' +
+               '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" size="30" type="text" value="new comment" />' +
                '</form>'
 
     assert_dom_equal expected, output_buffer
@@ -690,14 +694,32 @@ class FormHelperTest < ActionView::TestCase
 
     expected = '<form action="http://www.example.com" method="post">' +
                '<input name="post[title]" size="30" type="text" id="post_title" value="Hello World" />' +
-               '<input id="post_comments_attributes_321_name" name="post[comments_attributes][321][name]" size="30" type="text" value="comment #321" />' +
-               '<input id="post_comments_attributes_new_1_name" name="post[comments_attributes][new_1][name]" size="30" type="text" value="new comment" />' +
+               '<input id="post_comments_attributes_0_id" name="post[comments_attributes][0][id]" type="hidden" value="321" />' +
+               '<input id="post_comments_attributes_0_name" name="post[comments_attributes][0][name]" size="30" type="text" value="comment #321" />' +
+               '<input id="post_comments_attributes_1_name" name="post[comments_attributes][1][name]" size="30" type="text" value="new comment" />' +
                '</form>'
 
     assert_dom_equal expected, output_buffer
     assert_equal yielded_comments, @post.comments
   end
 
+  def test_nested_fields_for_with_child_index_option_override_on_a_nested_attributes_collection_association
+    @post.comments = []
+
+    form_for(:post, @post) do |f|
+      f.fields_for(:comments, Comment.new(321), :child_index => 'abc') do |cf|
+        concat cf.text_field(:name)
+      end
+    end
+
+    expected = '<form action="http://www.example.com" method="post">' +
+               '<input id="post_comments_attributes_abc_id" name="post[comments_attributes][abc][id]" type="hidden" value="321" />' +
+               '<input id="post_comments_attributes_abc_name" name="post[comments_attributes][abc][name]" size="30" type="text" value="comment #321" />' +
+               '</form>'
+
+    assert_dom_equal expected, output_buffer
+  end
+
   def test_fields_for
     fields_for(:post, @post) do |f|
       concat f.text_field(:title)