Store the transaction number in the transaction object

This avoids us having to manually increment and decrement it.

5 files changed, 30 insertions, 13 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
index 7cfaf3b0e5..5eb0f0f132 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb
@@ -198,7 +198,6 @@ module ActiveRecord
         @transaction_joinable = last_transaction_joinable
 
         if outside_transaction?
-          @open_transactions = 0
           @transaction = Transactions::Closed.new(self)
         elsif @transaction.open? && transaction_open
           begin
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
index 0a4649ffa7..4f1f9223ec 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
@@ -10,6 +10,10 @@ module ActiveRecord
       end
 
       class Closed < State
+        def number
+          0
+        end
+
         def begin
           Open.new(connection, self)
         end
@@ -33,16 +37,31 @@ module ActiveRecord
         def initialize(connection, parent)
           super connection
 
-          @parent  = parent
-          @records = []
+          @parent    = parent
+          @records   = []
+          @finishing = false
 
           if parent.open?
             connection.create_savepoint
           else
             connection.begin_db_transaction
           end
+        end
+
+        def number
+          if finishing?
+            parent.number
+          else
+            parent.number + 1
+          end
+        end
 
-          connection.increment_open_transactions
+        # Database adapters expect that #open_transactions will be decremented
+        # before we've actually executed a COMMIT or ROLLBACK. This is kinda
+        # annoying, but for now we use this @finishing flag to toggle what value
+        # #number should return.
+        def finishing?
+          @finishing
         end
 
         def begin
@@ -50,7 +69,7 @@ module ActiveRecord
         end
 
         def rollback
-          connection.decrement_open_transactions
+          @finishing = true
 
           if parent.open?
             connection.rollback_to_savepoint
@@ -63,7 +82,7 @@ module ActiveRecord
         end
 
         def commit
-          connection.decrement_open_transactions
+          @finishing = true
 
           begin
             if parent.open?
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index f7cb88331d..b7fcf0e512 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -4,6 +4,7 @@ require 'bigdecimal/util'
 require 'active_support/core_ext/benchmark'
 require 'active_record/connection_adapters/schema_cache'
 require 'monitor'
+require 'active_support/deprecation'
 
 module ActiveRecord
   module ConnectionAdapters # :nodoc:
@@ -69,7 +70,6 @@ module ActiveRecord
         @instrumenter        = ActiveSupport::Notifications.instrumenter
         @last_use            = false
         @logger              = logger
-        @open_transactions   = 0
         @pool                = pool
         @query_cache         = Hash.new { |h,sql| h[sql] = {} }
         @query_cache_enabled = false
@@ -237,14 +237,16 @@ module ActiveRecord
         @connection
       end
 
-      attr_reader :open_transactions
+      def open_transactions
+        @transaction.number
+      end
 
       def increment_open_transactions
-        @open_transactions += 1
+        ActiveSupport::Deprecation.warn "increment_open_transactions is deprecated and has no effect"
       end
 
       def decrement_open_transactions
-        @open_transactions -= 1
+        ActiveSupport::Deprecation.warn "decrement_open_transactions is deprecated and has no effect"
       end
 
       def transaction_joinable=(joinable)
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index d1751d70c6..76198b42ff 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -433,7 +433,6 @@ module ActiveRecord
       def reconnect!
         clear_cache!
         @connection.reset
-        @open_transactions = 0
         configure_connection
       end
 
diff --git a/activerecord/lib/active_record/railties/console_sandbox.rb b/activerecord/lib/active_record/railties/console_sandbox.rb
index 65a3d68619..90b462fad6 100644
--- a/activerecord/lib/active_record/railties/console_sandbox.rb
+++ b/activerecord/lib/active_record/railties/console_sandbox.rb
@@ -1,6 +1,4 @@
-ActiveRecord::Base.connection.increment_open_transactions
 ActiveRecord::Base.connection.begin_db_transaction
 at_exit do
   ActiveRecord::Base.connection.rollback_db_transaction
-  ActiveRecord::Base.connection.decrement_open_transactions
 end