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@@ -34,8 +34,10 @@ module ActiveRecord
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   #   person.name << 'by'
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   #   person.name_change    # => ['uncle bob', 'uncle bobby']
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   module Dirty
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+    DIRTY_SUFFIXES = ['_changed?', '_change', '_will_change!', '_was']
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+
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     def self.included(base)
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-      base.attribute_method_suffix '_changed?', '_change', '_will_change!', '_was'
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+      base.attribute_method_suffix *DIRTY_SUFFIXES
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       base.alias_method_chain :write_attribute, :dirty
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       base.alias_method_chain :save,            :dirty
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       base.alias_method_chain :save!,           :dirty
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@@ -44,6 +46,8 @@ module ActiveRecord
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       base.superclass_delegating_accessor :partial_updates
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       base.partial_updates = true
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+
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+      base.send(:extend, ClassMethods)
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     end
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     # Do any attributes have unsaved changes?
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@@ -161,5 +165,19 @@ module ActiveRecord
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         old != value
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       end
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+    module ClassMethods
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+      def self.extended(base)
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+        base.metaclass.alias_method_chain(:alias_attribute, :dirty)
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+      end
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+
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+      def alias_attribute_with_dirty(new_name, old_name)
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+        alias_attribute_without_dirty(new_name, old_name)
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+        DIRTY_SUFFIXES.each do |suffix|
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+          module_eval <<-STR, __FILE__, __LINE__+1
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+            def #{new_name}#{suffix}; self.#{old_name}#{suffix}; end
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+          STR
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+        end
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+      end
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+    end
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   end
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 end

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@@ -45,6 +45,19 @@ class DirtyTest < ActiveRecord::TestCase
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     assert_nil pirate.catchphrase_change
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   end
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+  def test_aliased_attribute_changes
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+    # the actual attribute here is name, title is an
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+    # alias setup via alias_attribute
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+    parrot = Parrot.new
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+    assert !parrot.title_changed?
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+    assert_nil parrot.title_change
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+
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+    parrot.name = 'Sam'
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+    assert parrot.title_changed?
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+    assert_nil parrot.title_was
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+    assert_equal parrot.name_change, parrot.title_change
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+  end
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+
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   def test_nullable_integer_not_marked_as_changed_if_new_value_is_blank
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     pirate = Pirate.new
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@@ -3,6 +3,7 @@ class Parrot < ActiveRecord::Base
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   has_and_belongs_to_many :pirates
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   has_and_belongs_to_many :treasures
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   has_many :loots, :as => :looter
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+  alias_attribute :title, :name
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 end
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 class LiveParrot < Parrot