Allow error_messages_for to report errors for multiple objects, as well as support for customizing the name of the object in the error summary header. Closes #4186. [andrew@redlinesoftware.com, Marcel Molina Jr.]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4287 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 85 insertions, 17 deletions

diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index 225d0c0319..c4615c2cc1 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,9 @@
 *SVN*
 
+* Allow error_messages_for to report errors for multiple objects, as well as support for customizing the name of the object in the error summary header. Closes #4186. [andrew@redlinesoftware.com, Marcel Molina Jr.]
+  
+  error_messages_for :account, :user, :subscription, :object_name => :account
+
 * Enhance documentation for setting headers in integration tests. Skip auto HTTP prepending when its already there. Closes #4079. [Rick Olson]
 
 * Documentation for AbstractRequest. Closes #4895. [kevin.clark@gmail.com] 
diff --git a/actionpack/lib/action_view/helpers/active_record_helper.rb b/actionpack/lib/action_view/helpers/active_record_helper.rb
index 828aebf790..c9d2c095bf 100644
--- a/actionpack/lib/action_view/helpers/active_record_helper.rb
+++ b/actionpack/lib/action_view/helpers/active_record_helper.rb
@@ -90,31 +90,45 @@ module ActionView
         end
       end
 
-      # Returns a string with a div containing all the error messages for the object located as an instance variable by the name
-      # of <tt>object_name</tt>. This div can be tailored by the following options:
+      # Returns a string with a div containing all of the error messages for the objects located as instance variables by the names
+      # given.  If more than one object is specified, the errors for the objects are displayed in the order that the object names are
+      # provided.
+      #
+      # This div can be tailored by the following options:
       #
       # * <tt>header_tag</tt> - Used for the header of the error div (default: h2)
       # * <tt>id</tt> - The id of the error div (default: errorExplanation)
       # * <tt>class</tt> - The class of the error div (default: errorExplanation)
+      # * <tt>object_name</tt> - The object name to use in the header, or
+      # any text that you prefer. If <tt>object_name</tt> is not set, the name of
+      # the first object will be used.
+      #
+      # Specifying one object:
+      # 
+      #   error_messages_for 'user'
+      #
+      # Specifying more than one object (and using the name 'user' in the
+      # header as the <tt>object_name</tt> instead of 'user_common'):
+      #
+      #   error_messages_for 'user_common', 'user', :object_name => 'user'
       #
       # NOTE: This is a pre-packaged presentation of the errors with embedded strings and a certain HTML structure. If what
       # you need is significantly different from the default presentation, it makes plenty of sense to access the object.errors
       # instance yourself and set it up. View the source of this method to see how easy it is.
-      def error_messages_for(object_name, options = {})
-        options = options.symbolize_keys
-        object = instance_variable_get("@#{object_name}")
-        if object && !object.errors.empty?
-          content_tag("div",
-            content_tag(
-              options[:header_tag] || "h2",
-              "#{pluralize(object.errors.count, "error")} prohibited this #{object_name.to_s.gsub("_", " ")} from being saved"
-            ) +
-            content_tag("p", "There were problems with the following fields:") +
-            content_tag("ul", object.errors.full_messages.collect { |msg| content_tag("li", msg) }),
-            "id" => options[:id] || "errorExplanation", "class" => options[:class] || "errorExplanation"
-          )
+      def error_messages_for(*params)
+        options = params.last.is_a?(Hash) ? params.pop.symbolize_keys : {}
+        objects = params.collect {|object_name| instance_variable_get("@#{object_name}") }.compact
+        count   = objects.inject(0) {|sum, object| sum + object.errors.count }
+        unless count.zero?
+          header_message = "#{pluralize(count, 'error')} prohibited this #{(options[:object_name] || params.first).to_s.gsub('_', ' ')} from being saved"
+          error_messages = objects.map {|object| object.errors.full_messages.map {|msg| content_tag(:li, msg) } }
+          content_tag(:div,
+            content_tag(options[:header_tag] || :h2, header_message) <<
+            content_tag(:p, 'There were problems with the following fields:') <<
+            content_tag(:ul, error_messages), 
+            :id => options[:id] || 'errorExplanation', :class => options[:class] || 'errorExplanation')
         else
-          ""
+          ''
         end
       end
 
diff --git a/actionpack/test/template/active_record_helper_test.rb b/actionpack/test/template/active_record_helper_test.rb
index e153e630ab..ffaae99e28 100644
--- a/actionpack/test/template/active_record_helper_test.rb
+++ b/actionpack/test/template/active_record_helper_test.rb
@@ -22,10 +22,16 @@ class ActiveRecordHelperTest < Test::Unit::TestCase
       alias_method :body_before_type_cast, :body unless respond_to?(:body_before_type_cast)
       alias_method :author_name_before_type_cast, :author_name unless respond_to?(:author_name_before_type_cast)
     end
+    
+    User = Struct.new("User", :email)
+    User.class_eval do
+      alias_method :email_before_type_cast, :email unless respond_to?(:email_before_type_cast)
+    end
+    
     Column = Struct.new("Column", :type, :name, :human_name)
   end
 
-  def setup
+  def setup_post
     @post = Post.new    
     def @post.errors
       Class.new {
@@ -50,6 +56,34 @@ class ActiveRecordHelperTest < Test::Unit::TestCase
     @post.body        = "Back to the hill and over it again!"
     @post.secret = 1
     @post.written_on  = Date.new(2004, 6, 15)
+  end
+  
+  def setup_user
+    @user = User.new    
+    def @user.errors
+      Class.new {
+        def on(field) field == "email" end
+        def empty?() false end 
+        def count() 1 end 
+        def full_messages() [ "User email can't be empty" ] end
+      }.new
+    end
+    
+    def @user.new_record?() true end
+    def @user.to_param() nil end
+
+    def @user.column_for_attribute(attr_name)
+      User.content_columns.select { |column| column.name == attr_name }.first
+    end
+
+    def User.content_columns() [ Column.new(:string, "email", "Email") ] end
+
+    @user.email = ""
+  end
+
+  def setup
+    setup_post
+    setup_user
 
     @controller = Object.new
     def @controller.url_for(options, *parameters_for_method_reference)
@@ -124,6 +158,22 @@ class ActiveRecordHelperTest < Test::Unit::TestCase
     assert_equal "", error_messages_for("notthere")
   end
 
+  def test_error_messages_for_many_objects
+    assert_dom_equal %(<div class="errorExplanation" id="errorExplanation"><h2>2 errors 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><li>User email can't be empty</li></ul></div>), error_messages_for("post", "user")
+
+    # reverse the order, error order changes and so does the title
+    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_messages_for("user", "post")
+
+    # add the default to put post back in the title
+    assert_dom_equal %(<div class="errorExplanation" id="errorExplanation"><h2>2 errors prohibited this post 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_messages_for("user", "post", :object_name => "post")
+    
+    # symbols work as well
+    assert_dom_equal %(<div class="errorExplanation" id="errorExplanation"><h2>2 errors prohibited this post 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_messages_for(:user, :post, :object_name => :post)
+    
+    # any default works too
+    assert_dom_equal %(<div class="errorExplanation" id="errorExplanation"><h2>2 errors prohibited this monkey 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_messages_for(:user, :post, :object_name => "monkey")
+  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>),