dirty.rb in activemodel-3.1.0.beta1

- old
+ new

@@ -1,17 +1,16 @@
 require 'active_model/attribute_methods'
-require 'active_support/concern'
 require 'active_support/hash_with_indifferent_access'
 require 'active_support/core_ext/object/duplicable'
 
 module ActiveModel
   # == Active Model Dirty
   #
   # Provides a way to track changes in your object in the same way as
   # Active Record does.
   #
-  # The requirements to implement ActiveModel::Dirty are to:
+  # The requirements for implementing ActiveModel::Dirty are:
   #
   # * <tt>include ActiveModel::Dirty</tt> in your object
   # * Call <tt>define_attribute_methods</tt> passing each method you want to
   #   track
   # * Call <tt>attr_name_will_change!</tt> before each change to the tracked
@@ -92,11 +91,11 @@
     included do
       attribute_method_suffix '_changed?', '_change', '_will_change!', '_was'
       attribute_method_affix :prefix => 'reset_', :suffix => '!'
     end
 
-    # Do any attributes have unsaved changes?
+    # Returns true if any attribute have unsaved changes, false otherwise.
     #   person.changed? # => false
     #   person.name = 'bob'
     #   person.changed? # => true
     def changed?
       !changed_attributes.empty?
@@ -113,10 +112,10 @@
     # Map of changed attrs => [original value, new value].
     #   person.changes # => {}
     #   person.name = 'bob'
     #   person.changes # => { 'name' => ['bill', 'bob'] }
     def changes
-      changed.inject(HashWithIndifferentAccess.new){ |h, attr| h[attr] = attribute_change(attr); h }
+      HashWithIndifferentAccess[changed.map { |attr| [attr, attribute_change(attr)] }]
     end
 
     # Map of attributes that were changed when the model was saved.
     #   person.name # => 'bob'
     #   person.name = 'robert'