friendly_id.rb in friendly_id4-4.0.0.beta3

- old
+ new
@@ -4,11 +4,36 @@
 require "friendly_id/configuration"
 require "friendly_id/finder_methods"
 
 # FriendlyId is a comprehensive Ruby library for ActiveRecord permalinks and
 # slugs.
+#
 # @author Norman Clarke
 module FriendlyId
   autoload :Slugged,  "friendly_id/slugged"
   autoload :Scoped,   "friendly_id/scoped"
   autoload :History,  "friendly_id/history"
+
+  # FriendlyId takes advantage of `extended` to do basic model setup, primarily
+  # extending FriendlyId::Base to add #friendly_id as a class method for
+  # configuring how a model is going to use FriendlyId. In previous versions of
+  # this library, ActiveRecord::Base was patched by default to include methods
+  # needed to configure friendly_id, but this version tries to be a little less
+  # invasive.
+  #
+  # In addition to adding the #friendly_id method, the class instance variable
+  # +@friendly_id_config+ is added. This variable is an instance of an anonymous
+  # subclass of FriendlyId::Configuration. This is done to allow for
+  # subsequently loaded modules like FriendlyId::Slugged to add functionality to
+  # the configuration only for the current class, and thereby isolating other
+  # classes from large feature changes a module could potentially introduce. The
+  # upshot of this is, you can have two Active Record models that both have a
+  # @friendly_id_config, but each config object can have different methods and
+  # behaviors depending on what modules have been loaded, without conflicts.
+  def self.extended(base)
+    base.instance_eval do
+      extend FriendlyId::Base
+      @friendly_id_config = Class.new(FriendlyId::Configuration).new(base)
+    end
+    ActiveRecord::Relation.send :include, FriendlyId::FinderMethods
+  end
 end