Adding a helper to render all messages stored on flash object.

actionpack/lib/action_view/helpers.rb

@@ -12,7 +12,8 @@ module Helpers #:nodoc:
     autoload :ControllerHelper
     autoload :CsrfHelper
     autoload :DateHelper
-    autoload :DebugHelper
+    autoload :DebugHelper  
+    autoload :FlashHelper
     autoload :FormHelper
     autoload :FormOptionsHelper
     autoload :FormTagHelper
@@ -42,7 +43,8 @@ module Helpers #:nodoc:
     include ControllerHelper
     include CsrfHelper
     include DateHelper
-    include DebugHelper
+    include DebugHelper   
+    include FlashHelper
     include FormHelper
     include FormOptionsHelper
     include FormTagHelper

actionpack/lib/action_view/helpers/flash_helper.rb

@@ -0,0 +1,69 @@
+module ActionView
+  module Helpers
+    module FlashHelper
+      # Helper to render all messages stored on +flash+ object. You can customize the output with the +options+ hash.
+      # 
+      # ==== Options
+      # * <tt>:with_parent_element</tt> - Sets the parent element that will be used on each message (defaults to :p).
+      # * <tt>:using_class</tt>         - Sets the class used on the parent element of each message (defaults to :flash).
+      #
+      # ==== Examples                 
+      # 
+      # On Controller:
+      #                
+      #   class PostsController < ApplicationController
+      #     def index
+      #       flash[:notice] = "Everything is ok :)"
+      #       flash[:alert] =  "Error :("
+      #     end
+      #   end
+      #      
+      # Then on the view:
+      # 
+      #   <%= flash_messages %>
+      #   # => <p class="flash flash_notice">Everything is ok :)</p>
+      #   #    <p class="flash flash_alert">Error :(</p>
+      # 
+      #   <%= flash_messages :with_parent_element => :div %>
+      #   # => <div class="flash flash_notice">Everything is ok :)</div>
+      #   #    <div class="flash flash_alert">Error :(</div>
+      # 
+      #   <%= flash_messages :using_class => :message %>
+      #   # => <p class="message message_notice">Everything is ok :)</p>
+      #   #    <p class="message message_alert">Error :(</p>
+      # 
+      #   <%= flash_messages :with_parent_element => :div, :using_class => :message %>
+      #   # => <div class="message message_notice">Everything is ok :)</div>
+      #   #    <div class="message message_alert">Error :(</div>   
+      # 
+      #   <%= flash_messages :using_class => :nil %>
+      #   # => <p>Everything is ok :)</p>
+      #   #    <p>Error :(</p>   
+      def flash_messages(options = {})
+        parent_element = options.delete(:with_parent_element) { :p }
+
+        messages = ""
+        options.default = "" # This is needed to use the key :using_class with nil value
+
+        flash.each do |key, value|                                                                 
+          parent_element_class = class_for_flash_message_parent_element(options.merge(:flash_message_key => key))
+
+          messages << content_tag(parent_element, :class => parent_element_class) { value } + "\n"
+        end
+
+        messages.html_safe
+      end      
+
+      protected
+        def class_for_flash_message_parent_element(options = {})
+          if options[:using_class]
+            parent_element_class = (options.delete(:using_class) { "flash" }).to_s
+
+            "#{parent_element_class} #{parent_element_class}_#{options[:flash_message_key]}"
+          else
+            nil
+          end
+        end
+    end
+  end
+end

actionpack/test/template/flash_helper_test.rb

@@ -0,0 +1,62 @@
+# encoding: utf-8
+
+require 'abstract_unit'
+
+class FlashHelperTest < ActionView::TestCase
+  tests ActionView::Helpers::FlashHelper
+
+  def test_flash_messages_without_messages
+    assert flash_messages.blank?
+  end         
+
+  def test_flash_messages_is_html_safe
+    flash[:notice] = "Some random resource was succesfuly saved."
+
+    assert flash_messages.html_safe?
+  end                  
+
+  def test_flash_messages_with_notice_message
+    flash[:notice] = "Everything is ok."
+
+    assert_equal %Q(<p class="flash flash_notice">Everything is ok.</p>\n), flash_messages    
+  end
+
+  def test_flash_messages_with_alert_message
+    flash[:alert] = "10 minutes to world explosion."
+
+    assert_equal %Q(<p class="flash flash_alert">10 minutes to world explosion.</p>\n), flash_messages    
+  end                               
+
+  def test_flash_messages_with_notice_and_alert_messages
+    flash[:notice] = "This application is just fine."
+    flash[:alert] = "The previous message is wrong!"
+
+    messages = flash_messages
+
+    assert messages.include?(%Q(<p class="flash flash_notice">This application is just fine.</p>\n))
+    messages.gsub!(%Q(<p class="flash flash_notice">This application is just fine.</p>\n), "")
+
+    assert messages.include?(%Q(<p class="flash flash_alert">The previous message is wrong!</p>\n))
+    messages.gsub!(%Q(<p class="flash flash_alert">The previous message is wrong!</p>\n), "")    
+
+    assert messages.blank?
+  end                     
+
+  def test_flash_messages_with_custom_parent_element
+    flash[:notice] = "Look at me mom, I'm on a flash message!"
+
+    assert_equal %Q(<div class="flash flash_notice">Look at me mom, I'm on a flash message!</div>\n), flash_messages(:with_parent_element => :div)
+  end
+
+  def test_flash_messages_with_custom_class_for_parent_element
+    flash[:alert] = "Houston, we have a problem."  
+
+    assert_equal %Q(<p class="message message_alert">Houston, we have a problem.</p>\n), flash_messages(:using_class => :message)    
+  end
+
+  def test_flash_messages_without_class_on_parent_element
+    flash[:notice] = "Up and running!"
+
+    assert_equal %Q(<p>Up and running!</p>\n), flash_messages(:using_class => nil)    
+  end
+end