5 files changed, 125 insertions, 1 deletions
diff --git a/activemodel/CHANGELOG.md b/activemodel/CHANGELOG.md
index 0d70edd0ba..42adbec8b9 100644
--- a/activemodel/CHANGELOG.md
+++ b/activemodel/CHANGELOG.md
@@ -1,3 +1,5 @@
+*   Added ActiveModel::Model, a mixin to make Ruby objects work with AP out of box *Guillermo Iguaran*
+
 *   `AM::Errors#to_json`: support `:full_messages` parameter *Bogdan Gusiev*
 
 *   Trim down Active Model API by removing `valid?` and `errors.full_messages` *José Valim*
@@ -61,7 +63,7 @@
 *   Add support for selectively enabling/disabling observers *Myron Marston*
 
 
-## Rails 3.0.12 (unreleased) ##
+## Rails 3.0.12 (March 1, 2012) ##
 
 *   No changes.
 
diff --git a/activemodel/README.rdoc b/activemodel/README.rdoc
index a7ba27ba73..9b121510a9 100644
--- a/activemodel/README.rdoc
+++ b/activemodel/README.rdoc
@@ -13,6 +13,25 @@ in code duplication and fragile applications that broke on upgrades. Active
 Model solves this by defining an explicit API. You can read more about the
 API in ActiveModel::Lint::Tests.
 
+Active Model provides a default module that implements the basic API required
+to integrate with Action Pack out of the box: +ActiveModel::Model+.
+
+    class Person
+      include ActiveModel::Model
+
+      attr_accessor :name, :age
+      validates_presence_of :name
+    end
+
+    person = Person.new(:name => 'bob', :age => '18')
+    person.name # => 'bob'
+    person.age # => 18
+    person.valid? # => false
+
+It includes model name instrospection, conversions, translations and
+validations, resulting in a class suitable to be used with ActionPack.
+See +ActiveModel::Model+ for more examples.
+
 Active Model also provides the following functionality to have ORM-like
 behavior out of the box:
 
diff --git a/activemodel/lib/active_model.rb b/activemodel/lib/active_model.rb
index 85514e63fd..2586147a20 100644
--- a/activemodel/lib/active_model.rb
+++ b/activemodel/lib/active_model.rb
@@ -39,6 +39,7 @@ module ActiveModel
   autoload :Errors
   autoload :Lint
   autoload :MassAssignmentSecurity
+  autoload :Model
   autoload :Name, 'active_model/naming'
   autoload :Naming
   autoload :Observer, 'active_model/observing'
diff --git a/activemodel/lib/active_model/model.rb b/activemodel/lib/active_model/model.rb
new file mode 100644
index 0000000000..8445113b64
--- /dev/null
+++ b/activemodel/lib/active_model/model.rb
@@ -0,0 +1,76 @@
+module ActiveModel
+
+  # == Active Model Basic Model
+  #
+  # Includes the required interface for an object to interact with +ActionPack+,
+  # using different +ActiveModel+ modules. It includes model name instrospection,
+  # conversions, translations and validations . Besides that, it allows you to
+  # initialize the object with a hash of attributes, pretty much like
+  # +ActiveRecord+ does.
+  #
+  # A minimal implementation could be:
+  #
+  #   class Person
+  #     include ActiveModel::Model
+  #     attr_accessor :name, :age
+  #   end
+  #
+  #   person = Person.new(:name => 'bob', :age => '18')
+  #   person.name # => 'bob'
+  #   person.age # => 18
+  #
+  # Note that, by default, +ActiveModel::Model+ implements +persisted?+ to
+  # return +false+, which is the most common case. You may want to override it
+  # in your class to simulate a different scenario:
+  #
+  #   class Person
+  #     include ActiveModel::Model
+  #     attr_accessor :id, :name
+  #
+  #     def persisted?
+  #       self.id == 1
+  #     end
+  #   end
+  #
+  #   person = Person.new(:id => 1, :name => 'bob')
+  #   person.persisted? # => true
+  #
+  # Also, if for some reason you need to run code on +initialize+, make sure you
+  # call super if you want the attributes hash initialization to happen.
+  #
+  #   class Person
+  #     include ActiveModel::Model
+  #     attr_accessor :id, :name, :omg
+  #
+  #     def initialize(attributes)
+  #       super
+  #       @omg ||= true
+  #     end
+  #   end
+  #
+  #   person = Person.new(:id => 1, :name => 'bob')
+  #   person.omg # => true
+  #
+  # For more detailed information on other functionality available, please refer
+  # to the specific modules included in +ActiveModel::Model+ (see below).
+  module Model
+    def self.included(base)
+      base.class_eval do
+        extend  ActiveModel::Naming
+        extend  ActiveModel::Translation
+        include ActiveModel::Validations
+        include ActiveModel::Conversion
+      end
+    end
+
+    def initialize(params={})
+      params.each do |attr, value|
+        self.public_send("#{attr}=", value)
+      end if params
+    end
+
+    def persisted?
+      false
+    end
+  end
+end
diff --git a/activemodel/test/cases/model_test.rb b/activemodel/test/cases/model_test.rb
new file mode 100644
index 0000000000..d93fd96b88
--- /dev/null
+++ b/activemodel/test/cases/model_test.rb
@@ -0,0 +1,26 @@
+require 'cases/helper'
+
+class ModelTest < ActiveModel::TestCase
+  include ActiveModel::Lint::Tests
+
+  class BasicModel
+    include ActiveModel::Model
+    attr_accessor :attr
+  end
+
+  def setup
+    @model = BasicModel.new
+  end
+
+  def test_initialize_with_params
+    object = BasicModel.new(:attr => "value")
+    assert_equal object.attr, "value"
+  end
+
+  def test_initialize_with_nil_or_empty_hash_params_does_not_explode
+    assert_nothing_raised do
+      BasicModel.new()
+      BasicModel.new({})
+    end
+  end
+end