Always abort a transaction that raised an exception.

src/ZODB/tests/Synchronization.py

@@ -67,9 +67,10 @@ class SynchronizedStorage:
         apply(self.assertRaises, args)
 
     def verifyWrongTrans(self, callable, *args):
-        self._storage.tpc_begin(Transaction())
-        args = (StorageTransactionError, callable) + args
-        apply(self.assertRaises, args)
+        t = Transaction()
+        self._storage.tpc_begin(t)
+        self.assertRaises(StorageTransactionError, callable, *args)
+        self._storage.tpc_abort(t)
 
     def checkAbortVersionNotCommitting(self):
         self.verifyNotCommitting(self._storage.abortVersion,

src/ZODB/tests/VersionStorage.py

@@ -199,9 +199,12 @@ class VersionStorage:
         eq(zodb_unpickle(data), MinPO(54))
         t = Transaction()
         self._storage.tpc_begin(t)
-        self.assertRaises(POSException.VersionCommitError,
-                          self._storage.commitVersion,
-                          'one', 'one', t)
+        try:
+            self.assertRaises(POSException.VersionCommitError,
+                              self._storage.commitVersion,
+                              'one', 'one', t)
+        finally:
+            self._storage.tpc_abort(t)
 
     def checkModifyAfterAbortVersion(self):
         eq = self.assertEqual