when "pop-ing" current savepoint name - consider open transaction count

- this allows us to work with user marked savepoints as intended, since they will likely execute within a single AR transaction object
- but at the same time AR's nested transaction emulation (using savepoints) will work in a Rails compatible way (fixes #477)

Author: kares

lib/arjdbc/jdbc/adapter.rb

@@ -402,8 +402,15 @@ def release_savepoint(name = current_savepoint_name)
       # @since 1.3.0
       # @override
       def current_savepoint_name(create = nil)
-        return "active_record_#{open_transactions}" if create
-        @connection.marked_savepoint_names.last || "active_record_#{open_transactions}"
+        open_tx = open_transactions
+        return "active_record_#{open_tx}" if create
+
+        sp_names = @connection.marked_savepoint_names
+        unless sp_names.empty?
+          sp_names[ -(sp_names.size - open_tx + 1) ]
+        else
+          "active_record_#{open_tx}"
+        end
       end
 
       # Executes a SQL query in the context of this connection using the bind

test/db/sqlite3/transaction_test.rb

@@ -44,49 +44,4 @@ def test_supports_savepoints
     assert_true ActiveRecord::Base.connection.supports_savepoints?
   end
 
-  def test_many_savepoints
-    @first = Entry.create
-    Entry.transaction do
-      @first.content = "One"
-      @first.save!
-
-      begin
-        Entry.transaction :requires_new => true do
-          @first.content = "Two"
-          @first.save!
-
-          begin
-            Entry.transaction :requires_new => true do
-              @first.content = "Three"
-              @first.save!
-
-              begin
-                Entry.transaction :requires_new => true do
-                  @first.content = "Four"
-                  @first.save!
-                  raise
-                end
-              rescue
-              end
-
-              @three = @first.reload.content
-              raise
-            end
-          rescue
-          end
-
-          @two = @first.reload.content
-          raise
-        end
-      rescue
-      end
-
-      @one = @first.reload.content
-    end
-
-    assert_equal "One", @one
-    assert_equal "Two", @two
-    assert_equal "Three", @three
-  end
-
 end

test/transaction.rb

@@ -107,6 +107,52 @@ def test_transaction_isolation_repeatable_read
 #    end
 #  end if Test::Unit::TestCase.ar_version('4.0')
 
+  def test_transaction_nesting
+    @first = Entry.create
+
+    Entry.transaction do
+      @first.content = "One"
+      @first.save!
+
+      begin
+        Entry.transaction :requires_new => true do
+          @first.content = "Two"
+          @first.save!
+
+          begin
+            Entry.transaction :requires_new => true do
+              @first.content = "Three"
+              @first.save!
+
+              begin
+                Entry.transaction :requires_new => true do
+                  @first.content = "Four"
+                  @first.save!
+                  raise
+                end
+              rescue
+              end
+
+              @three = @first.reload.content
+              raise
+            end
+          rescue
+          end
+
+          @two = @first.reload.content
+          raise
+        end
+      rescue
+      end
+
+      @one = @first.reload.content
+    end
+
+    assert_equal "One", @one
+    assert_equal "Two", @two
+    assert_equal "Three", @three
+  end
+
   def test_savepoint
     omit 'savepoins not supported' unless @supports_savepoints
     Entry.create! :title => '1'
@@ -175,7 +221,7 @@ def test_named_savepoint
 
         assert_equal 4, Entry.count
 
-        connection.rollback_to_savepoint
+        connection.rollback_to_savepoint 'SP2'
         assert_equal 3, Entry.count
 
         connection.create_savepoint 'SP3'