Make counter cache work when replacing an association (closes #3245). Thanks for the patch!

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3762 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

1 files changed, 11 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/associations/belongs_to_association.rb b/activerecord/lib/active_record/associations/belongs_to_association.rb
index 804a7ebf21..3e0e0d0fb9 100644
--- a/activerecord/lib/active_record/associations/belongs_to_association.rb
+++ b/activerecord/lib/active_record/associations/belongs_to_association.rb
@@ -10,11 +10,22 @@ module ActiveRecord
       end
 
       def replace(record)
+        counter_cache_name = @reflection.counter_cache_column
+
         if record.nil?
+          if counter_cache_name && @owner[counter_cache_name] && !@owner.new_record?
+            @reflection.klass.decrement_counter(counter_cache_name, @owner[@reflection.primary_key_name]) if @owner[@reflection.primary_key_name]
+          end
+
           @target = @owner[@reflection.primary_key_name] = nil
         else
           raise_on_type_mismatch(record)
 
+          if counter_cache_name && @owner[counter_cache_name] && !@owner.new_record?
+            @reflection.klass.increment_counter(counter_cache_name, record.id)
+            @reflection.klass.decrement_counter(counter_cache_name, @owner[@reflection.primary_key_name]) if @owner[@reflection.primary_key_name]
+          end
+
           @target = (AssociationProxy === record ? record.target : record)
           @owner[@reflection.primary_key_name] = record.id unless record.new_record?
           @updated = true