Warn when transaction context manager ends on inactive transaction

if .rollback() or .commit() is called inside the transaction
context manager, the transaction object is deactivated.
the context manager continues but will not be able to correctly
fulfill it's closing state.  Ensure a warning is emitted when
this happens.

Change-Id: I8fc3a73f7c21575dda5bcbd6fb74ddb679771630

1 files changed, 20 insertions, 1 deletions

diff --git a/test/engine/test_transaction.py b/test/engine/test_transaction.py
index 164604cd6..b82d143f9 100644
--- a/test/engine/test_transaction.py
+++ b/test/engine/test_transaction.py
@@ -320,6 +320,22 @@ class TransactionTest(fixtures.TestBase):
             1,
         )
 
+    def test_deactivated_warning_ctxmanager(self, local_connection):
+        with expect_warnings(
+            "transaction already deassociated from connection"
+        ):
+            with local_connection.begin() as trans:
+                trans.rollback()
+
+    @testing.requires.savepoints
+    def test_deactivated_savepoint_warning_ctxmanager(self, local_connection):
+        with expect_warnings(
+            "nested transaction already deassociated from connection"
+        ):
+            with local_connection.begin():
+                with local_connection.begin_nested() as savepoint:
+                    savepoint.rollback()
+
     def test_commit_fails_flat(self, local_connection):
         connection = local_connection
 
@@ -355,7 +371,10 @@ class TransactionTest(fixtures.TestBase):
 
         t1 = transaction[0]
         assert not t1.is_active
-        t1.rollback()  # no error
+        with expect_warnings(
+            "transaction already deassociated from connection"
+        ):
+            t1.rollback()  # no error
 
     @testing.requires.savepoints_w_release
     def test_savepoint_rollback_fails_flat(self, local_connection):