1 files changed, 156 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
new file mode 100644
index 0000000000..2117eae5cb
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/abstract/transaction.rb
@@ -0,0 +1,156 @@
+module ActiveRecord
+  module ConnectionAdapters
+    class Transaction #:nodoc:
+      attr_reader :connection
+
+      def initialize(connection)
+        @connection = connection
+      end
+    end
+
+    class ClosedTransaction < Transaction #:nodoc:
+      def number
+        0
+      end
+
+      def begin
+        RealTransaction.new(connection, self)
+      end
+
+      def closed?
+        true
+      end
+
+      def open?
+        false
+      end
+
+      def joinable?
+        false
+      end
+
+      # This is a noop when there are no open transactions
+      def add_record(record)
+      end
+    end
+
+    class OpenTransaction < Transaction #:nodoc:
+      attr_reader :parent, :records
+      attr_writer :joinable
+
+      def initialize(connection, parent)
+        super connection
+
+        @parent    = parent
+        @records   = []
+        @finishing = false
+        @joinable  = true
+      end
+
+      # This state is necesarry so that we correctly handle stuff that might
+      # happen in a commit/rollback. But it's kinda distasteful. Maybe we can
+      # find a better way to structure it in the future.
+      def finishing?
+        @finishing
+      end
+
+      def joinable?
+        @joinable && !finishing?
+      end
+
+      def number
+        if finishing?
+          parent.number
+        else
+          parent.number + 1
+        end
+      end
+
+      def begin
+        if finishing?
+          parent.begin
+        else
+          SavepointTransaction.new(connection, self)
+        end
+      end
+
+      def rollback
+        @finishing = true
+        perform_rollback
+        parent
+      end
+
+      def commit
+        @finishing = true
+        perform_commit
+        parent
+      end
+
+      def add_record(record)
+        records << record
+      end
+
+      def rollback_records
+        records.uniq.each do |record|
+          begin
+            record.rolledback!(parent.closed?)
+          rescue => e
+            record.logger.error(e) if record.respond_to?(:logger) && record.logger
+          end
+        end
+      end
+
+      def commit_records
+        records.uniq.each do |record|
+          begin
+            record.committed!
+          rescue => e
+            record.logger.error(e) if record.respond_to?(:logger) && record.logger
+          end
+        end
+      end
+
+      def closed?
+        false
+      end
+
+      def open?
+        true
+      end
+    end
+
+    class RealTransaction < OpenTransaction #:nodoc:
+      def initialize(connection, parent)
+        super
+        connection.begin_db_transaction
+      end
+
+      def perform_rollback
+        connection.rollback_db_transaction
+        rollback_records
+      end
+
+      def perform_commit
+        connection.commit_db_transaction
+        commit_records
+      end
+    end
+
+    class SavepointTransaction < OpenTransaction #:nodoc:
+      def initialize(connection, parent)
+        super
+        connection.create_savepoint
+      end
+
+      def perform_rollback
+        connection.rollback_to_savepoint
+        rollback_records
+      end
+
+      def perform_commit
+        connection.release_savepoint
+        records.each { |r| parent.add_record(r) }
+      end
+    end
+  end
+end