1 files changed, 109 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/model.rb b/activerecord/lib/active_record/model.rb
new file mode 100644
index 0000000000..86de5ab2fa
--- /dev/null
+++ b/activerecord/lib/active_record/model.rb
@@ -0,0 +1,109 @@
+require 'active_support/deprecation'
+
+module ActiveRecord
+  # <tt>ActiveRecord::Model</tt> can be included into a class to add Active Record persistence.
+  # This is an alternative to inheriting from <tt>ActiveRecord::Base</tt>. Example:
+  #
+  #     class Post
+  #       include ActiveRecord::Model
+  #     end
+  #
+  module Model
+    module ClassMethods #:nodoc:
+      include ActiveSupport::Callbacks::ClassMethods
+      include ActiveModel::Naming
+      include QueryCache::ClassMethods
+      include ActiveSupport::Benchmarkable
+      include ActiveSupport::DescendantsTracker
+
+      include Querying
+      include Translation
+      include DynamicMatchers
+      include CounterCache
+      include Explain
+      include ConnectionHandling
+    end
+
+    def self.included(base)
+      return if base.singleton_class < ClassMethods
+
+      base.class_eval do
+        extend ClassMethods
+        Callbacks::Register.setup(self)
+        initialize_generated_modules unless self == Base
+      end
+    end
+
+    extend ActiveModel::Configuration
+    extend ActiveModel::Callbacks
+    extend ActiveModel::MassAssignmentSecurity::ClassMethods
+    extend ActiveModel::AttributeMethods::ClassMethods
+    extend Callbacks::Register
+    extend Explain
+    extend ConnectionHandling
+
+    def self.extend(*modules)
+      ClassMethods.send(:include, *modules)
+    end
+
+    include Persistence
+    include ReadonlyAttributes
+    include ModelSchema
+    include Inheritance
+    include Scoping
+    include Sanitization
+    include Integration
+    include AttributeAssignment
+    include ActiveModel::Conversion
+    include Validations
+    include Locking::Optimistic, Locking::Pessimistic
+    include AttributeMethods
+    include Callbacks, ActiveModel::Observing, Timestamp
+    include Associations
+    include IdentityMap
+    include ActiveModel::SecurePassword
+    include AutosaveAssociation, NestedAttributes
+    include Aggregations, Transactions, Reflection, Serialization, Store
+    include Core
+
+    class << self
+      def arel_engine
+        self
+      end
+
+      def abstract_class?
+        false
+      end
+
+      def inheritance_column
+        'type'
+      end
+    end
+
+    module DeprecationProxy #:nodoc:
+      class << self
+        instance_methods.each { |m| undef_method m unless m =~ /^__|^object_id$|^instance_eval$/ }
+
+        def method_missing(name, *args, &block)
+          if Model.respond_to?(name)
+            Model.send(name, *args, &block)
+          else
+            ActiveSupport::Deprecation.warn(
+              "The object passed to the active_record load hook was previously ActiveRecord::Base " \
+              "(a Class). Now it is ActiveRecord::Model (a Module). You have called `#{name}' which " \
+              "is only defined on ActiveRecord::Base. Please change your code so that it works with " \
+              "a module rather than a class. (Model is included in Base, so anything added to Model " \
+              "will be available on Base as well.)"
+            )
+            Base.send(name, *args, &block)
+          end
+        end
+
+        alias send method_missing
+      end
+    end
+  end
+
+  # Load Base at this point, because the active_record load hook is run in that file.
+  Base
+end