create a transaction object and point AR objects at that object during a

transaction.

activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb

@@ -193,7 +193,8 @@ module ActiveRecord
         rescue Exception => database_transaction_rollback
           if transaction_open && !outside_transaction?
             transaction_open = false
-            decrement_open_transactions
+            txn = decrement_open_transactions
+            txn.aborted!
             if open_transactions == 0
               rollback_db_transaction
               rollback_transaction_records(true)
@@ -208,9 +209,10 @@ module ActiveRecord
         @transaction_joinable = last_transaction_joinable
 
         if outside_transaction?
-          @open_transactions = 0
+          @current_transaction = nil
         elsif transaction_open
-          decrement_open_transactions
+          txn = decrement_open_transactions
+          txn.committed!
           begin
             if open_transactions == 0
               commit_db_transaction

activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

@@ -69,6 +69,7 @@ module ActiveRecord
         @last_use            = false
         @logger              = logger
         @open_transactions   = 0
+        @current_transaction = nil
         @pool                = pool
         @query_cache         = Hash.new { |h,sql| h[sql] = {} }
         @query_cache_enabled = false
@@ -236,14 +237,30 @@ module ActiveRecord
         @connection
       end
 
-      attr_reader :open_transactions
+      def open_transactions
+        count = 0
+        txn   = current_transaction
+
+        while txn
+          count += 1
+          txn = txn.next
+        end
+
+        count
+      end
+
+      attr_reader :current_transaction
 
       def increment_open_transactions
-        @open_transactions += 1
+        @current_transaction = Transaction.new(current_transaction)
       end
 
       def decrement_open_transactions
-        @open_transactions -= 1
+        return unless current_transaction
+
+        txn = current_transaction
+        @current_transaction = txn.next
+        txn
       end
 
       def transaction_joinable=(joinable)

activerecord/lib/active_record/core.rb

@@ -393,6 +393,7 @@ module ActiveRecord
       @marked_for_destruction  = false
       @new_record              = true
       @mass_assignment_options = nil
+      @txn                     = nil
       @_start_transaction_state = {}
     end
   end

activerecord/lib/active_record/transactions.rb

@@ -1,6 +1,32 @@
 require 'thread'
 
 module ActiveRecord
+  class Transaction
+    attr_reader :next
+
+    def initialize(txn = nil)
+      @next      = txn
+      @committed = false
+      @aborted   = false
+    end
+
+    def committed!
+      @committed = true
+    end
+
+    def aborted!
+      @aborted = true
+    end
+
+    def committed?
+      @committed
+    end
+
+    def aborted?
+      @aborted
+    end
+  end
+
   # See ActiveRecord::Transactions::ClassMethods for documentation.
   module Transactions
     extend ActiveSupport::Concern
@@ -307,11 +333,11 @@ module ActiveRecord
     def with_transaction_returning_status
       status = nil
       self.class.transaction do
+        @txn = self.class.connection.current_transaction
         add_to_transaction
         begin
           status = yield
         rescue ActiveRecord::Rollback
-          @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) - 1
           status = nil
         end
 
@@ -327,20 +353,17 @@ module ActiveRecord
       @_start_transaction_state[:id] = id if has_attribute?(self.class.primary_key)
       @_start_transaction_state[:new_record] = @new_record
       @_start_transaction_state[:destroyed] = @destroyed
-      @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) + 1
     end
 
     # Clear the new record state and id of a record.
     def clear_transaction_record_state #:nodoc:
-      @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) - 1
-      @_start_transaction_state.clear if @_start_transaction_state[:level] < 1
+      @_start_transaction_state.clear if @txn.committed?
     end
 
     # Restore the new record state and id of a record that was previously saved by a call to save_record_state.
     def restore_transaction_record_state(force = false) #:nodoc:
       unless @_start_transaction_state.empty?
-        @_start_transaction_state[:level] = (@_start_transaction_state[:level] || 0) - 1
-        if @_start_transaction_state[:level] < 1 || force
+        if @txn.aborted? || force
           restore_state = @_start_transaction_state
           was_frozen = @attributes.frozen?
           @attributes = @attributes.dup if was_frozen