Added the first part of Simply Helpful to core. The rest is pending a clean integartion of polymorphic urls [DHH]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@6633 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

8 files changed, 300 insertions, 1 deletions

diff --git a/actionpack/CHANGELOG b/actionpack/CHANGELOG
index 9a676d5d8b..6142b42c0d 100644
--- a/actionpack/CHANGELOG
+++ b/actionpack/CHANGELOG
@@ -1,5 +1,20 @@
 *SVN*
 
+* Added RecordTagHelper for using RecordIdentifier conventions on divs and other container elements [DHH]. Example:
+
+    <% div_for(post) do %>     <div id="post_45" class="post">
+      <%= post.body %>           What a wonderful world!
+    <% end %>                  </div>
+
+* Added page[record] accessor to JavaScriptGenerator that relies on RecordIdentifier to find the right dom id [DHH]. Example:
+
+    format.js do
+      # Calls: new Effect.fade('post_45');
+      render(:update) { |page| page[post].visual_effect(:fade) }
+    end
+
+* Added RecordIdentifier to enforce view conventions on records for dom ids, classes, and partial paths [DHH]
+
 * Added map.namespace to deal with the common situation of admin sections and the like [DHH]
 
     Before:
diff --git a/actionpack/lib/action_controller.rb b/actionpack/lib/action_controller.rb
index cabcae866b..a0bdf4995c 100755
--- a/actionpack/lib/action_controller.rb
+++ b/actionpack/lib/action_controller.rb
@@ -54,6 +54,7 @@ require 'action_controller/verification'
 require 'action_controller/streaming'
 require 'action_controller/session_management'
 require 'action_controller/components'
+require 'action_controller/record_identifier'
 require 'action_controller/macros/auto_complete'
 require 'action_controller/macros/in_place_editing'
 
@@ -76,6 +77,7 @@ ActionController::Base.class_eval do
   include ActionController::Streaming
   include ActionController::SessionManagement
   include ActionController::Components
+  include ActionController::RecordIdentifier
   include ActionController::Macros::AutoComplete
   include ActionController::Macros::InPlaceEditing
 end
diff --git a/actionpack/lib/action_controller/record_identifier.rb b/actionpack/lib/action_controller/record_identifier.rb
new file mode 100644
index 0000000000..1247665a8b
--- /dev/null
+++ b/actionpack/lib/action_controller/record_identifier.rb
@@ -0,0 +1,91 @@
+module ActionController  
+  # The record identifier encapsulates a number of naming conventions for dealing with records, like Active Records or 
+  # Active Resources or pretty much any other model type that has an id. These patterns are then used to try elevate
+  # the view actions to a higher logical level. Example:
+  #
+  #   # routes
+  #   map.resources :posts
+  #
+  #   # view
+  #   <% div_for(post) do %>     <div id="post_45" class="post">
+  #     <%= post.body %>           What a wonderful world!
+  #   <% end %>                  </div>
+  #
+  #   # controller
+  #   def destroy
+  #     post = Post.find(params[:id])
+  #     post.destroy
+  #
+  #     respond_to do |format|
+  #       format.html { redirect_to(post) } # Calls polymorphic_url(post) which in turn calls post_url(post)
+  #       format.js do
+  #         # Calls: new Effect.fade('post_45');
+  #         render(:update) { |page| page[post].visual_effect(:fade) }
+  #       end
+  #     end
+  #   end
+  #
+  # As the example above shows, you can stop caring to a large extend what the actual id of the post is. You just know
+  # that one is being assigned and that the subsequent calls in redirect_to and the RJS expect that same naming 
+  # convention and allows you to write less code if you follow it.
+  module RecordIdentifier
+    extend self
+
+    # Returns plural/singular for a record or class. Example:
+    #
+    #   partial_path(post)   # => "posts/post"
+    #   partial_path(Person) # => "people/person"
+    def partial_path(record_or_class)
+      klass = class_from_record_or_class(record_or_class)
+      "#{klass.name.tableize}/#{klass.name.demodulize.underscore}"
+    end
+
+    # The DOM class convention is to use the singular form of an object or class. Examples:
+    #
+    #   dom_class(post)   # => "post"
+    #   dom_class(Person) # => "person"
+    #
+    # If you need to address multiple instances of the same class in the same view, you can prefix the dom_class:
+    #
+    #   dom_class(post, :edit)   # => "edit_post"
+    #   dom_class(Person, :edit) # => "edit_person"
+    def dom_class(record_or_class, prefix = nil)
+      [ prefix, singular_class_name(record_or_class) ].compact * '_'
+    end
+
+    # The DOM class convention is to use the singular form of an object or class with the id following an underscore. 
+    # If no id is found, prefix with "new_" instead. Examples:
+    #
+    #   dom_class(Post.new(:id => 45)) # => "post_45"
+    #   dom_class(Post.new)            # => "new_post"
+    #
+    # If you need to address multiple instances of the same class in the same view, you can prefix the dom_id:
+    #
+    #   dom_class(Post.new(:id => 45), :edit) # => "edit_post_45"
+    def dom_id(record, prefix = nil) 
+      prefix ||= 'new' unless record.id 
+      [ prefix, singular_class_name(record), record.id ].compact * '_'
+    end
+
+    # Returns the plural class name of a record or class. Examples:
+    #
+    #   plural_class_name(post)             # => "posts"
+    #   plural_class_name(Highrise::Person) # => "highrise_people"
+    def plural_class_name(record_or_class)
+      singular_class_name(record_or_class).pluralize
+    end
+
+    # Returns the singular class name of a record or class. Examples:
+    #
+    #   singular_class_name(post)             # => "post"
+    #   singular_class_name(Highrise::Person) # => "highrise_person"
+    def singular_class_name(record_or_class)
+      class_from_record_or_class(record_or_class).name.underscore.tr('/', '_')
+    end
+
+    private
+      def class_from_record_or_class(record_or_class)
+        record_or_class.is_a?(Class) ? record_or_class : record_or_class.class
+      end
+  end
+end
\ No newline at end of file
diff --git a/actionpack/lib/action_view/helpers/prototype_helper.rb b/actionpack/lib/action_view/helpers/prototype_helper.rb
index ed3f7b7d7f..9fa27d6386 100644
--- a/actionpack/lib/action_view/helpers/prototype_helper.rb
+++ b/actionpack/lib/action_view/helpers/prototype_helper.rb
@@ -384,8 +384,19 @@ module ActionView
           #   page['blank_slate']                  # => $('blank_slate');
           #   page['blank_slate'].show             # => $('blank_slate').show();
           #   page['blank_slate'].show('first').up # => $('blank_slate').show('first').up();
+          #
+          # You can also pass in a record, which will use ActionController::RecordIdentifier.dom_id to lookup
+          # the correct id:
+          #
+          #   page[@post]     # => $('post_45')
+          #   page[Post.new]  # => $('new_post')
           def [](id)
-            JavaScriptElementProxy.new(self, id)
+            case id
+              when String, Symbol, NilClass
+                JavaScriptElementProxy.new(self, id)
+              else
+                JavaScriptElementProxy.new(self, ActionController::RecordIdentifier.dom_id(id))
+            end
           end
           
           # Returns an object whose <tt>#to_json</tt> evaluates to +code+. Use this to pass a literal JavaScript 
diff --git a/actionpack/lib/action_view/helpers/record_identification_helper.rb b/actionpack/lib/action_view/helpers/record_identification_helper.rb
new file mode 100644
index 0000000000..2e5ff865cc
--- /dev/null
+++ b/actionpack/lib/action_view/helpers/record_identification_helper.rb
@@ -0,0 +1,16 @@
+module RecordIdentificationHelper
+  # See ActionController::RecordIdentifier.partial_path -- this is just a delegate to that for convenient access in the view.
+  def partial_path(*args, &block)
+    ActionController::RecordIdentifier.partial_path(*args, &block)
+  end
+
+  # See ActionController::RecordIdentifier.dom_class -- this is just a delegate to that for convenient access in the view.
+  def dom_class(*args, &block)
+    ActionController::RecordIdentifier.dom_class(*args, &block)
+  end
+
+  # See ActionController::RecordIdentifier.dom_id -- this is just a delegate to that for convenient access in the view.
+  def dom_id(*args, &block)
+    ActionController::RecordIdentifier.dom_id(*args, &block)
+  end
+end
\ No newline at end of file
diff --git a/actionpack/lib/action_view/helpers/record_tag_helper.rb b/actionpack/lib/action_view/helpers/record_tag_helper.rb
new file mode 100644
index 0000000000..29845ba147
--- /dev/null
+++ b/actionpack/lib/action_view/helpers/record_tag_helper.rb
@@ -0,0 +1,55 @@
+module RecordTagHelper
+  # Produces a wrapper DIV element with id and class parameters that
+  # relate to the specified ActiveRecord object. Usage example:
+  #
+  #    <% div_for(@person, :class => "foo") do %>
+  #       <%=h @person.name %>
+  #    <% end %>
+  #
+  # produces:
+  #
+  #    <div id="person_123" class="person foo"> Joe Bloggs </div>
+  #
+  def div_for(record, *args, &block)
+    content_tag_for(:div, record, *args, &block)
+  end
+  
+  # content_tag_for creates an HTML element with id and class parameters
+  # that relate to the specified ActiveRecord object. For example:
+  #
+  #    <% content_tag_for(:tr, @person) do %>
+  #      <td><%=h @person.first_name %></td>
+  #      <td><%=h @person.last_name %></td>
+  #    <% end %>
+  #
+  # would produce hthe following HTML (assuming @person is an instance of
+  # a Person object, with an id value of 123):
+  #
+  #    <tr id="person_123" class="person">....</tr>
+  #
+  # If you require the HTML id attribute to have a prefix, you can specify it:
+  #
+  #    <% content_tag_for(:tr, @person, :foo) do %> ...
+  #
+  # produces:
+  #    
+  #    <tr id="foo_person_123" class="person">...
+  #
+  # content_tag_for also accepts a hash of options, which will be converted to
+  # additional HTML attributes. If you specify a +:class+ value, it will be combined
+  # with the default class name for your object. For example:
+  #
+  #    <% content_tag_for(:li, @person, :class => "bar") %>...
+  #
+  # produces:
+  #
+  #    <li id="person_123" class="person bar">...
+  #
+  def content_tag_for(tag_name, record, *args, &block)
+    prefix  = args.first.is_a?(Hash) ? nil : args.shift
+    options = args.first.is_a?(Hash) ? args.shift : {}
+    concat content_tag(tag_name, capture(&block), 
+      options.merge({ :class => "#{dom_class(record)} #{options[:class]}".strip, :id => dom_id(record, prefix) })), 
+      block.binding
+  end
+end
\ No newline at end of file
diff --git a/actionpack/test/controller/record_identifier_test.rb b/actionpack/test/controller/record_identifier_test.rb
new file mode 100644
index 0000000000..d805a4a385
--- /dev/null
+++ b/actionpack/test/controller/record_identifier_test.rb
@@ -0,0 +1,102 @@
+require File.dirname(__FILE__) + '/../abstract_unit'
+
+class Post
+  attr_reader :id
+  def save; @id = 1 end
+  def new_record?; @id.nil? end
+  def name
+    @id.nil? ? 'new post' : "post ##{@id}"
+  end
+  class Nested < Post; end
+end
+
+class Test::Unit::TestCase
+  protected
+    def posts_url
+      'http://www.example.com/posts'
+    end
+    
+    def post_url(post)
+      "http://www.example.com/posts/#{post.id}"
+    end
+end
+
+
+class RecordIdentifierTest < Test::Unit::TestCase
+  include ActionController::RecordIdentifier
+
+  def setup
+    @klass  = Post
+    @record = @klass.new
+    @singular = 'post'
+    @plural = 'posts'
+  end
+
+  def test_dom_id_with_new_record
+    assert_equal "new_#{@singular}", dom_id(@record)
+  end
+
+  def test_dom_id_with_new_record_and_prefix
+    assert_equal "custom_prefix_#{@singular}", dom_id(@record, :custom_prefix)
+  end
+
+  def test_dom_id_with_saved_record
+    @record.save
+    assert_equal "#{@singular}_1", dom_id(@record)
+  end
+
+  def test_dom_id_with_prefix
+    @record.save
+    assert_equal "edit_#{@singular}_1", dom_id(@record, :edit)
+  end
+
+  def test_partial_path
+    expected = "#{@plural}/#{@singular}"
+    assert_equal expected, partial_path(@record)
+    assert_equal expected, partial_path(Post)
+  end
+
+  def test_dom_class
+    assert_equal @singular, dom_class(@record)
+  end
+  
+  def test_dom_class_with_prefix
+    assert_equal "custom_prefix_#{@singular}", dom_class(@record, :custom_prefix)
+  end
+
+  def test_singular_class_name
+    assert_equal @singular, singular_class_name(@record)
+  end
+
+  def test_singular_class_name_for_class
+    assert_equal @singular, singular_class_name(@klass)
+  end
+
+  def test_plural_class_name
+    assert_equal @plural, plural_class_name(@record)
+  end
+
+  def test_plural_class_name_for_class
+    assert_equal @plural, plural_class_name(@klass)
+  end
+
+  private
+    def method_missing(method, *args)
+      RecordIdentifier.send(method, *args)
+    end
+end
+
+class NestedRecordIdentifierTest < RecordIdentifierTest
+  def setup
+    @klass  = Post::Nested
+    @record = @klass.new
+    @singular = 'post_nested'
+    @plural = 'post_nesteds'
+  end
+
+  def test_partial_path
+    expected = "post/nesteds/nested"
+    assert_equal expected, partial_path(@record)
+    assert_equal expected, partial_path(Post::Nested)
+  end
+end
\ No newline at end of file
diff --git a/actionpack/test/template/prototype_helper_test.rb b/actionpack/test/template/prototype_helper_test.rb
index cc8b650039..ef658517ff 100644
--- a/actionpack/test/template/prototype_helper_test.rb
+++ b/actionpack/test/template/prototype_helper_test.rb
@@ -1,5 +1,7 @@
 require "#{File.dirname(__FILE__)}/../abstract_unit"
 
+Bunny = Struct.new(:Bunny, :id)
+
 module BaseTest
   include ActionView::Helpers::JavaScriptHelper
   include ActionView::Helpers::PrototypeHelper
@@ -253,6 +255,11 @@ Element.update("baz", "<p>This is a test</p>");
     assert_equal %($("hello");), @generator['hello']
   end
 
+  def test_element_access_on_records
+    assert_equal %($("bunny_5");),   @generator[Bunny.new(:id => 5)]
+    assert_equal %($("new_bunny");), @generator[Bunny.new]
+  end
+
   def test_element_proxy_one_deep
     @generator['hello'].hide
     assert_equal %($("hello").hide();), @generator.to_s