From acf371511d2ade25f91ca89909e8f6a14495da71 Mon Sep 17 00:00:00 2001
From: Carlos Antonio da Silva <carlosantoniodasilva@gmail.com>
Date: Thu, 24 Jun 2010 17:36:54 -0300
Subject: [PATCH] Do not wrap hidden fields with error proc

---
 .../lib/action_view/helpers/active_model_helper.rb |   18 ++++++++++++++++--
 actionpack/lib/action_view/helpers/form_helper.rb  |    1 -
 .../test/template/active_model_helper_test.rb      |    7 +++++++
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/actionpack/lib/action_view/helpers/active_model_helper.rb b/actionpack/lib/action_view/helpers/active_model_helper.rb
index 0f9b04c..6bb0875 100644
--- a/actionpack/lib/action_view/helpers/active_model_helper.rb
+++ b/actionpack/lib/action_view/helpers/active_model_helper.rb
@@ -36,12 +36,16 @@ module ActionView
         end
       end
 
-      %w(tag content_tag to_date_select_tag to_datetime_select_tag to_time_select_tag).each do |meth|
+      %w(content_tag to_date_select_tag to_datetime_select_tag to_time_select_tag).each do |meth|
         module_eval "def #{meth}(*) error_wrapping(super) end", __FILE__, __LINE__
       end
 
+      def tag(type, options, *)
+        tag_generate_errors?(options) ? error_wrapping(super) : super
+      end
+
       def error_wrapping(html_tag)
-        if object.respond_to?(:errors) && object.errors.respond_to?(:full_messages) && object.errors[@method_name].any?
+        if object_has_errors?
           Base.field_error_proc.call(html_tag, self)
         else
           html_tag
@@ -51,6 +55,16 @@ module ActionView
       def error_message
         object.errors[@method_name]
       end
+
+      private
+
+      def object_has_errors?
+        object.respond_to?(:errors) && object.errors.respond_to?(:full_messages) && error_message.any?
+      end
+
+      def tag_generate_errors?(options)
+        options['type'] != 'hidden'
+      end
     end
 
     class FormBuilder
diff --git a/actionpack/lib/action_view/helpers/form_helper.rb b/actionpack/lib/action_view/helpers/form_helper.rb
index 2bbe11f..d1b10a9 100644
--- a/actionpack/lib/action_view/helpers/form_helper.rb
+++ b/actionpack/lib/action_view/helpers/form_helper.rb
@@ -124,7 +124,6 @@ module ActionView
       # model:
       #
       #   <%= form_for :person do |f| %>
-      #     <%= f.error_messages %>
       #     First name: <%= f.text_field :first_name %><br />
       #     Last name : <%= f.text_field :last_name %><br />
       #     Biography : <%= f.text_area :biography %><br />
diff --git a/actionpack/test/template/active_model_helper_test.rb b/actionpack/test/template/active_model_helper_test.rb
index b170507..6ab244d 100644
--- a/actionpack/test/template/active_model_helper_test.rb
+++ b/actionpack/test/template/active_model_helper_test.rb
@@ -39,6 +39,13 @@ class ActiveModelHelperTest < ActionView::TestCase
     )
   end
 
+  def test_hidden_field_does_not_render_errors
+    assert_dom_equal(
+      %(<input id="post_author_name" name="post[author_name]" type="hidden" value="" />),
+      hidden_field("post", "author_name")
+    )
+  end
+
   def test_field_error_proc
     old_proc = ActionView::Base.field_error_proc
     ActionView::Base.field_error_proc = Proc.new do |html_tag, instance|
-- 
1.7.0