Fix acts_as_list such that moving next-to-last item to the bottom does not result in duplicate positions

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@1872 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 7 insertions, 5 deletions

diff --git a/activerecord/lib/active_record/acts/list.rb b/activerecord/lib/active_record/acts/list.rb
index 29b5a0a58e..f3cb3496d8 100644
--- a/activerecord/lib/active_record/acts/list.rb
+++ b/activerecord/lib/active_record/acts/list.rb
@@ -163,17 +163,19 @@ module ActiveRecord
           # Overwrite this method to define the scope of the list changes
           def scope_condition() "1" end
 
-          def bottom_position_in_list
-            item = bottom_item
+          def bottom_position_in_list(except = nil)
+            item = bottom_item(except)
             item ? item.send(position_column) : 0
           end
 
-          def bottom_item
-            self.class.find(:first, :conditions => scope_condition, :order => "#{position_column} DESC")
+          def bottom_item(except = nil)
+            conditions = scope_condition
+            conditions = "#{conditions} AND id != #{except.id}" if except
+            self.class.find(:first, :conditions => conditions, :order => "#{position_column} DESC")
           end
 
           def assume_bottom_position
-            update_attribute(position_column, bottom_position_in_list.to_i + 1) unless last?
+            update_attribute(position_column, bottom_position_in_list(self).to_i + 1)
           end
   
           def assume_top_position