Added that Active Records will automatically record creation and/or update timestamps of database objects if fields of the names created_at/created_on or updated_at/updated_on are present. [Tobias Luetke] Added acts_as_tree that can decorates an existing class with a many to many relationship with itself. Added acts_as_list that can decorates an existing class with methods like move_higher/lower, move_to_top/bottom.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@176 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

7 files changed, 220 insertions, 229 deletions

diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index 844dc20b9b..bbbac02af1 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,5 +1,18 @@
 *CVS*
 
+* Added acts_as_list that can decorates an existing class with methods like move_higher/lower, move_to_top/bottom. Example:
+
+    class TodoItem < ActiveRecord::Base
+      acts_as_list :scope => :todo_list_id
+      belongs_to :todo_list
+    end
+
+* Added acts_as_tree that can decorates an existing class with a many to many relationship with itself. Perfect for categories in 
+  categories and the likes.
+
+* Added that Active Records will automatically record creation and/or update timestamps of database objects if fields of the names 
+  created_at/created_on or updated_at/updated_on are present. [Tobias Luetke]
+
 * Added Base.default_error_messages as a hash of all the error messages used in the validates_*_of so they can be changed in one place [Tobias Luetke]
 
 * Added automatic transaction block around AssociationCollection.<<, AssociationCollection.delete, and AssociationCollection.destroy_all
@@ -98,32 +111,6 @@
         end
     end
 
-* Added ActiveRecord::Mixins::Touch that will record creation and update times of objects [xal]. Example:
-
-    class Bill < ActiveRecord::Base
-      include ActiveRecord::Mixins::Touch
-    end
-  
-    bill = Bill.create("amount" => 100)
-    bill.created_at # => Time.now at the moment of Bill.create
-    bill.updated_at # => Time.now at the moment of Bill.create
-  
-    bill.update_attribute("amount", 150)
-    bill.created_at # => Time.now at the moment of Bill.create
-    bill.updated_at # => Time.now at the moment of bill.update_attribute
-  
-* Added ActiveRecord::Mixins::List that can decorates an existing class with methods like move_higher/lower, move_to_top/bottom. Example:
-
-    class TodoItem < ActiveRecord::Base
-      include ActiveRecord::Mixins::List
-      belongs_to :todo_list
-   
-      private
-        def scope_condition
-          "todo_list_id = #{todo_list_id}"
-        end
-    end
-
 * Added the option for sanitizing find_by_sql and the offset parts in regular finds [Sam Stephenson]. Examples:
 
     Project.find_all ["category = ?", category_name], "created ASC", ["? OFFSET ?", 15, 20]
@@ -244,6 +231,7 @@
 
 * All associations will now attempt to require the classes that they associate to. Relieving the need for most explicit 'require' statements.
 
+
 *1.1.0* (34)
 
 * Added automatic fixture setup and instance variable availability. Fixtures can also be automatically 
diff --git a/activerecord/lib/active_record.rb b/activerecord/lib/active_record.rb
index 2ed18b3313..229983503e 100755
--- a/activerecord/lib/active_record.rb
+++ b/activerecord/lib/active_record.rb
@@ -35,6 +35,9 @@ require 'active_record/associations'
 require 'active_record/aggregations'
 require 'active_record/transactions'
 require 'active_record/reflection'
+require 'active_record/timestamp'
+require 'active_record/mixins/list'
+require 'active_record/mixins/tree'
 
 ActiveRecord::Base.class_eval do
   include ActiveRecord::Validations
@@ -43,11 +46,11 @@ ActiveRecord::Base.class_eval do
   include ActiveRecord::Aggregations
   include ActiveRecord::Transactions
   include ActiveRecord::Reflection
+  include ActiveRecord::Timestamp
+  include ActiveRecord::Mixins::Tree
+  include ActiveRecord::Mixins::List
 end
 
-require 'active_record/mixins/list'
-require 'active_record/mixins/touch'
-
 require 'active_record/connection_adapters/mysql_adapter'
 require 'active_record/connection_adapters/postgresql_adapter'
 require 'active_record/connection_adapters/sqlite_adapter'
diff --git a/activerecord/lib/active_record/mixins/list.rb b/activerecord/lib/active_record/mixins/list.rb
index bec4b33651..16a60d7b6c 100644
--- a/activerecord/lib/active_record/mixins/list.rb
+++ b/activerecord/lib/active_record/mixins/list.rb
@@ -28,141 +28,156 @@ module ActiveRecord
     #   todo_list.last.move_higher
     module List
       def self.append_features(base)
-        super        
-        base.before_destroy :remove_from_list
-        base.after_create   :add_to_list_bottom
+        super
+        base.extend(ClassMethods)
       end
       
-      # can be overriden
-      
-      def position_column
-        "position"
-      end
+      module ClassMethods
+        def acts_as_list(options = {})
+          configuration = { :column => "position", :scope => "1" }
+          configuration.update(options) if options.is_a?(Hash)
+          
+          class_eval <<-EOV
+            include InstanceMethods
 
-      # Moving around on the list
+            def position_column
+              '#{configuration[:column]}'
+            end
 
-      def move_lower
-        return unless lower_item
-
-        self.class.transaction do
-          lower_item.decrement_position
-          increment_position
+            def scope_condition
+              "#{configuration[:scope]} = \#{#{configuration[:scope]}}"
+            end
+            
+            before_destroy :remove_from_list
+            after_create   :add_to_list_bottom
+          EOV
         end
-      end
+        
+        module InstanceMethods
+          def move_lower
+            return unless lower_item
 
-      def move_higher
-        return unless higher_item
+            self.class.transaction do
+              lower_item.decrement_position
+              increment_position
+            end
+          end
 
-        self.class.transaction do
-          higher_item.increment_position
-          decrement_position
-        end
-      end
+          def move_higher
+            return unless higher_item
+
+            self.class.transaction do
+              higher_item.increment_position
+              decrement_position
+            end
+          end
     
-      def move_to_bottom
-        self.class.transaction do
-          decrement_positions_on_lower_items
-          assume_bottom_position
-        end
-      end
+          def move_to_bottom
+            self.class.transaction do
+              decrement_positions_on_lower_items
+              assume_bottom_position
+            end
+          end
 
-      def move_to_top
-        self.class.transaction do
-          increment_positions_on_higher_items
-          assume_top_position
-        end
-      end
+          def move_to_top
+            self.class.transaction do
+              increment_positions_on_higher_items
+              assume_top_position
+            end
+          end
     
 
-      # Entering or existing the list
+          # Entering or existing the list
     
-      def add_to_list_top
-        increment_positions_on_all_items
-      end
+          def add_to_list_top
+            increment_positions_on_all_items
+          end
 
-      def add_to_list_bottom
-        assume_bottom_position
-      end
+          def add_to_list_bottom
+            assume_bottom_position
+          end
 
-      def remove_from_list
-        decrement_positions_on_lower_items
-      end
+          def remove_from_list
+            decrement_positions_on_lower_items
+          end
 
 
-      # Changing the position
+          # Changing the position
 
-      def increment_position
-        update_attribute position_column, self.send(position_column).to_i + 1
-      end
+          def increment_position
+            update_attribute position_column, self.send(position_column).to_i + 1
+          end
     
-      def decrement_position
-        update_attribute position_column, self.send(position_column).to_i - 1
-      end
+          def decrement_position
+            update_attribute position_column, self.send(position_column).to_i - 1
+          end
     
     
-      # Querying the position
+          # Querying the position
     
-      def first?
-        self.send(position_column) == 1
-      end
+          def first?
+            self.send(position_column) == 1
+          end
     
-      def last?
-        self.send(position_column) == bottom_position_in_list
-      end
+          def last?
+            self.send(position_column) == bottom_position_in_list
+          end
 
-      private
-        # Overwrite this method to define the scope of the list changes
-        def scope_condition() "1" end
+          private
+            # Overwrite this method to define the scope of the list changes
+            def scope_condition() "1" end
     
-        def higher_item
-          self.class.find_first(
-            "#{scope_condition} AND #{position_column} = #{(send(position_column).to_i - 1).to_s}"
-          )
-        end
+            def higher_item
+              self.class.find_first(
+                "#{scope_condition} AND #{position_column} = #{(send(position_column).to_i - 1).to_s}"
+              )
+            end
     
-        def lower_item
-          self.class.find_first(
-            "#{scope_condition} AND #{position_column} = #{(send(position_column).to_i + 1).to_s}"
-          )
-        end
+            def lower_item
+              self.class.find_first(
+                "#{scope_condition} AND #{position_column} = #{(send(position_column).to_i + 1).to_s}"
+              )
+            end
     
-        def bottom_position_in_list
-          item = bottom_item
-          item ? item.send(position_column) : 0
-        end
+            def bottom_position_in_list
+              item = bottom_item
+              item ? item.send(position_column) : 0
+            end
     
-        def bottom_item
-          self.class.find_first(
-            "#{scope_condition} ",
-            "#{position_column} DESC"
-          )
-        end
+            def bottom_item
+              self.class.find_first(
+                "#{scope_condition} ",
+                "#{position_column} DESC"
+              )
+            end
 
-        def assume_bottom_position
-          update_attribute position_column, bottom_position_in_list.to_i + 1
-        end
+            def assume_bottom_position
+              update_attribute position_column, bottom_position_in_list.to_i + 1
+            end
       
-        def assume_top_position
-          update_attribute position_column, 1
-        end
+            def assume_top_position
+              update_attribute position_column, 1
+            end
       
-        def decrement_positions_on_lower_items
-          self.class.update_all(
-            "#{position_column} = (#{position_column} - 1)",  "#{scope_condition} AND #{position_column} > #{send(position_column).to_i}"
-          )
-        end
+            def decrement_positions_on_lower_items
+              self.class.update_all(
+                "#{position_column} = (#{position_column} - 1)",  "#{scope_condition} AND #{position_column} > #{send(position_column).to_i}"
+              )
+            end
       
-        def increment_positions_on_higher_items
-          self.class.update_all(
-            "#{position_column} = (#{position_column} + 1)",  "#{scope_condition} AND #{position_column} < #{send(position_column)}"
-          )
-        end
+            def increment_positions_on_higher_items
+              self.class.update_all(
+                "#{position_column} = (#{position_column} + 1)",  "#{scope_condition} AND #{position_column} < #{send(position_column)}"
+              )
+            end
 
-        def increment_positions_on_all_items
-          self.class.update_all(
-            "#{position_column} = (#{position_column} + 1)",  "#{scope_condition}"
-          )
-        end
+            def increment_positions_on_all_items
+              self.class.update_all(
+                "#{position_column} = (#{position_column} + 1)",  "#{scope_condition}"
+              )
+            end
+        end     
+      end
     end
   end
 end
\ No newline at end of file
diff --git a/activerecord/lib/active_record/mixins/touch.rb b/activerecord/lib/active_record/mixins/touch.rb
deleted file mode 100644
index baf217542a..0000000000
--- a/activerecord/lib/active_record/mixins/touch.rb
+++ /dev/null
@@ -1,34 +0,0 @@
-module ActiveRecord
-  module Mixins
-    # Including this mixins will record when objects of the class are created in a datetime column called "created_at"
-    # and when its updated in another datetime column called "updated_at".
-    #
-    #   class Bill < ActiveRecord::Base
-    #     include ActiveRecord::Mixins::Touch
-    #   end
-    #
-    #   bill = Bill.create("amount" => 100)
-    #   bill.created_at # => Time.now at the moment of Bill.create
-    #   bill.updated_at # => Time.now at the moment of Bill.create
-    #
-    #   bill.update_attribute("amount", 150)
-    #   bill.created_at # => Time.now at the moment of Bill.create
-    #   bill.updated_at # => Time.now at the moment of bill.update_attribute
-    module Touch
-      def self.append_features(base)
-        super
-
-        base.before_create :touch_on_create
-        base.before_update :touch_on_update
-      end  
-
-      def touch_on_create
-        self.updated_at = (self.created_at ||= Time.now)
-      end
-
-      def touch_on_update
-        self.updated_at = Time.now
-      end
-    end
-  end
-end
\ No newline at end of file
diff --git a/activerecord/lib/active_record/mixins/tree.rb b/activerecord/lib/active_record/mixins/tree.rb
index 582aa09b4b..141bbb1806 100644
--- a/activerecord/lib/active_record/mixins/tree.rb
+++ b/activerecord/lib/active_record/mixins/tree.rb
@@ -21,16 +21,20 @@ module ActiveRecord
     #   root.children # => [child1]
     #   root.children.first.children.first # => subchild1
     module Tree
-
       def self.append_features(base)
         super        
-
-        base.module_eval <<-associations
-          belongs_to  :parent,    :class_name => name, :foreign_key => "parent_id"        
-          has_many    :children,  :class_name => name, :foreign_key => "parent_id", :order => "id", :dependent => true
-        associations
-              
+        base.extend(ClassMethods)              
       end  
     end
+    
+    module ClassMethods
+      def acts_as_tree(options = {})
+        configuration = { :foreign_key => "parent_id", :order => nil }
+        configuration.update(options) if options.is_a?(Hash)
+        
+        belongs_to :parent, :class_name => name, :foreign_key => configuration[:foreign_key]
+        has_many :children, :class_name => name, :foreign_key => configuration[:foreign_key], :order => configuration[:order], :dependent => true
+      end
+    end
   end
 end
\ No newline at end of file
diff --git a/activerecord/test/fixtures/mixin.rb b/activerecord/test/fixtures/mixin.rb
index 589c1a8c23..8cae604140 100644
--- a/activerecord/test/fixtures/mixin.rb
+++ b/activerecord/test/fixtures/mixin.rb
@@ -1,21 +1,13 @@
 class Mixin < ActiveRecord::Base
-  include ActiveRecord::Mixins::Touch
-  include ActiveRecord::Mixins::Tree
+  acts_as_tree :foreign_key => "parent_id", :order => "id"
+
 end
 
 class ListMixin < ActiveRecord::Base
-  include ActiveRecord::Mixins::List
-   
+  acts_as_list :column => "pos", :scope => :parent_id
+
   def self.table_name
     "mixins"
   end
     
-  def scope_condition
-     "parent_id = #{self.parent_id}"
-  end      
-  
-  def position_column
-    "pos"
-  end
-
 end
\ No newline at end of file
diff --git a/activerecord/test/mixin_test.rb b/activerecord/test/mixin_test.rb
index cc56bc7cec..31e71f5d6c 100644
--- a/activerecord/test/mixin_test.rb
+++ b/activerecord/test/mixin_test.rb
@@ -4,6 +4,73 @@ require 'active_record/mixins/list'
 require 'active_record/mixins/touch'
 require 'fixtures/mixin'
 
+
+class ListTest < Test::Unit::TestCase
+  fixtures :mixins
+  
+  def test_injection
+    l = ListMixin.new("parent_id"=>1)
+    assert_equal "parent_id = 1", l.scope_condition
+    assert_equal "pos", l.position_column
+
+  end
+  
+  def test_reordering
+    
+    assert_equal [ListMixin.find(2), ListMixin.find(3)], ListMixin.find_all("parent_id=1", "pos")
+    
+    ListMixin.find(2).move_lower
+    
+    assert_equal [ListMixin.find(3), ListMixin.find(2)], ListMixin.find_all("parent_id=1", "pos")
+    
+    ListMixin.find(2).move_higher
+
+    assert_equal [ListMixin.find(2), ListMixin.find(3)], ListMixin.find_all("parent_id=1", "pos")
+    
+  end
+
+  def test_insert          
+    new = ListMixin.create("parent_id"=>5)
+    assert_equal 1, new.pos
+    assert new.first?
+    assert new.last?
+
+    new = ListMixin.create("parent_id"=>5)
+    assert_equal 2, new.pos
+    assert !new.first?
+    assert new.last?
+    
+    new = ListMixin.create("parent_id"=>5)
+    assert_equal 3, new.pos    
+    assert !new.first?
+    assert new.last?
+    
+    new = ListMixin.create("parent_id"=>10)
+    assert_equal 1, new.pos
+    assert new.first?
+    assert new.last?
+  end  
+  
+  
+  def test_delete_middle
+    first = ListMixin.create("parent_id"=>5)
+    assert_equal 1, first.pos
+
+    second = ListMixin.create("parent_id"=>5)
+    assert_equal 2, second.pos
+    
+    third = ListMixin.create("parent_id"=>5)
+    assert_equal 3, third.pos    
+    
+    second.destroy
+    
+    assert_equal 1, @mixins["first"].find.pos
+    assert_equal 2, @mixins["third"].find.pos
+    
+  end  
+
+end
+
 class TreeTest < Test::Unit::TestCase
   fixtures :mixins
   
@@ -54,48 +121,4 @@ class TouchTest < Test::Unit::TestCase
     assert_not_nil @obj.updated_at
     assert_not_nil @obj.created_at
   end  
-  
-  
 end
-
-
-class ListTest < Test::Unit::TestCase
-  fixtures :mixins
-  
-  def test_reordering
-    
-    assert_equal [ListMixin.find(2), ListMixin.find(3)], ListMixin.find_all("parent_id=1", "pos")
-    
-    ListMixin.find(2).move_lower
-    
-    assert_equal [ListMixin.find(3), ListMixin.find(2)], ListMixin.find_all("parent_id=1", "pos")
-    
-    ListMixin.find(2).move_higher
-
-    assert_equal [ListMixin.find(2), ListMixin.find(3)], ListMixin.find_all("parent_id=1", "pos")
-    
-  end
-
-  def test_insert
-    new = ListMixin.create("parent_id"=>3)
-    assert_equal 1, new.pos
-    assert new.first?
-    assert new.last?
-
-    new = ListMixin.create("parent_id"=>3)
-    assert_equal 2, new.pos
-    assert !new.first?
-    assert new.last?
-    
-    new = ListMixin.create("parent_id"=>3)
-    assert_equal 3, new.pos    
-    assert !new.first?
-    assert new.last?
-    
-    new = ListMixin.create("parent_id"=>2)
-    assert_equal 1, new.pos
-    assert new.first?
-    assert new.last?
-
-  end  
-end
\ No newline at end of file