Add support for error_messages_for(@obj)

4 files changed, 41 insertions, 9 deletions

diff --git a/actionpack/lib/action_view/helpers/active_model_helper.rb b/actionpack/lib/action_view/helpers/active_model_helper.rb
index 0f122d9232..4fd7f7d83c 100644
--- a/actionpack/lib/action_view/helpers/active_model_helper.rb
+++ b/actionpack/lib/action_view/helpers/active_model_helper.rb
@@ -160,11 +160,24 @@ module ActionView
       #
       #   error_messages_for 'user'
       #
+      # You can also supply an object:
+      #
+      #   error_messages_for @user
+      #
+      # This will use the last part of the model name in the presentation. For instance, if
+      # this is a MyKlass::User object, this will use "user" as the name in the String. This
+      # is taken from MyKlass::User.model_name.human, which can be overridden.
+      #
       # To specify more than one object, you simply list them; optionally, you can add an extra <tt>:object_name</tt> parameter, which
       # will be the name used in the header message:
       #
       #   error_messages_for 'user_common', 'user', :object_name => 'user'
       #
+      # You can also use a number of objects, which will have the same naming semantics
+      # as a single object.
+      #
+      #   error_messages_for @user, @post
+      #
       # If the objects cannot be located as instance variables, you can add an extra <tt>:object</tt> parameter which gives the actual
       # object (or array of objects to use):
       #
@@ -176,15 +189,20 @@ module ActionView
       def error_messages_for(*params)
         options = params.extract_options!.symbolize_keys
 
-        if object = options.delete(:object)
-          objects = [object].flatten
-        else
-          objects = params.collect {|object_name| instance_variable_get("@#{object_name}") }.compact
+        objects = Array.wrap(options.delete(:object) || params).map do |object|
+          unless object.respond_to?(:to_model)
+            object = instance_variable_get("@#{object}")
+            object = convert_to_model(object)
+          else
+            object = object.to_model
+            options[:object_name] ||= object.class.model_name.human
+          end
+          object
         end
 
-        objects.map! {|o| convert_to_model(o) }
+        objects.compact!
 
-        count  = objects.inject(0) {|sum, object| sum + object.errors.count }
+        count = objects.inject(0) {|sum, object| sum + object.errors.count }
         unless count.zero?
           html = {}
           [:id, :class].each do |key|
diff --git a/actionpack/test/template/active_record_helper_i18n_test.rb b/actionpack/test/template/active_record_helper_i18n_test.rb
index 63032e4e5c..047f81be29 100644
--- a/actionpack/test/template/active_record_helper_i18n_test.rb
+++ b/actionpack/test/template/active_record_helper_i18n_test.rb
@@ -3,11 +3,14 @@ require 'abstract_unit'
 class ActiveRecordHelperI18nTest < Test::Unit::TestCase
   include ActionView::Context
   include ActionView::Helpers::ActiveModelHelper
-  
+
   attr_reader :request
 
   def setup
     @object = stub :errors => stub(:count => 1, :full_messages => ['full_messages'])
+    @object.stubs :to_model => @object
+    @object.stubs :class => stub(:model_name => stub(:human => ""))
+
     @object_name = 'book_seller'
     @object_name_without_underscore = 'book seller'
 
@@ -39,7 +42,7 @@ class ActiveRecordHelperI18nTest < Test::Unit::TestCase
     I18n.expects(:t).with('', :default => '', :count => 1, :scope => [:activerecord, :models]).once.returns ''
     error_messages_for(:object => @object, :locale => 'en')
   end
-  
+
   def test_error_messages_for_given_object_name_it_translates_object_name
     I18n.expects(:t).with(:header, :locale => 'en', :scope => [:activerecord, :errors, :template], :count => 1, :model => @object_name_without_underscore).returns "1 error prohibited this #{@object_name_without_underscore} from being saved"
     I18n.expects(:t).with(@object_name, :default => @object_name_without_underscore, :count => 1, :scope => [:activerecord, :models]).once.returns @object_name_without_underscore
diff --git a/actionpack/test/template/active_record_helper_test.rb b/actionpack/test/template/active_record_helper_test.rb
index b07ce6cf5d..ec3384f15d 100644
--- a/actionpack/test/template/active_record_helper_test.rb
+++ b/actionpack/test/template/active_record_helper_test.rb
@@ -295,6 +295,16 @@ class ActiveRecordHelperTest < ActionView::TestCase
     assert_equal '', error_messages_for('user', :object => nil)
   end
 
+  def test_error_messages_for_model_objects
+    error = error_messages_for(@post)
+    assert_dom_equal %(<div class="errorExplanation" id="errorExplanation"><h2>1 error prohibited this post from being saved</h2><p>There were problems with the following fields:</p><ul><li>Author name can't be empty</li></ul></div>),
+      error
+
+    error = error_messages_for(@user, @post)
+    assert_dom_equal %(<div class="errorExplanation" id="errorExplanation"><h2>2 errors prohibited this user from being saved</h2><p>There were problems with the following fields:</p><ul><li>User email can't be empty</li><li>Author name can't be empty</li></ul></div>),
+      error
+  end
+
   def test_form_with_string_multipart
     assert_dom_equal(
       %(<form action="create" enctype="multipart/form-data" method="post"><p><label for="post_title">Title</label><br /><input id="post_title" name="post[title]" size="30" type="text" value="Hello World" /></p>\n<p><label for="post_body">Body</label><br /><div class="fieldWithErrors"><textarea cols="40" id="post_body" name="post[body]" rows="20">Back to the hill and over it again!</textarea></div></p><input name="commit" type="submit" value="Create" /></form>),
diff --git a/activemodel/lib/active_model/naming.rb b/activemodel/lib/active_model/naming.rb
index ffb44e3824..b8c2a367b4 100644
--- a/activemodel/lib/active_model/naming.rb
+++ b/activemodel/lib/active_model/naming.rb
@@ -2,7 +2,7 @@ require 'active_support/inflector'
 
 module ActiveModel
   class Name < String
-    attr_reader :singular, :plural, :element, :collection, :partial_path
+    attr_reader :singular, :plural, :element, :collection, :partial_path, :human
     alias_method :cache_key, :collection
 
     def initialize(name)
@@ -10,6 +10,7 @@ module ActiveModel
       @singular = ActiveSupport::Inflector.underscore(self).tr('/', '_').freeze
       @plural = ActiveSupport::Inflector.pluralize(@singular).freeze
       @element = ActiveSupport::Inflector.underscore(ActiveSupport::Inflector.demodulize(self)).freeze
+      @human = @element.gsub(/_/, " ")
       @collection = ActiveSupport::Inflector.tableize(self).freeze
       @partial_path = "#{@collection}/#{@element}".freeze
     end