Fixed #22343 -- Disallowed select_for_update in autocommit mode

The ticket was originally about two failing tests, which are
fixed by putting their queries in transactions.

Thanks Tim Graham for the report, Aymeric Augustin for the fix,
and Simon Charette, Tim Graham & Loïc Bistuer for review.

1 files changed, 24 insertions, 2 deletions

diff --git a/tests/select_for_update/tests.py b/tests/select_for_update/tests.py
index a4136d7a16..54ba0d1d27 100644
--- a/tests/select_for_update/tests.py
+++ b/tests/select_for_update/tests.py
@@ -77,7 +77,8 @@ class SelectForUpdateTests(TransactionTestCase):
         Test that the backend's FOR UPDATE variant appears in
         generated SQL when select_for_update is invoked.
         """
-        list(Person.objects.all().select_for_update())
+        with transaction.atomic():
+            list(Person.objects.all().select_for_update())
         self.assertTrue(self.has_for_update_sql(connection))
 
     @skipUnlessDBFeature('has_select_for_update_nowait')
@@ -86,7 +87,8 @@ class SelectForUpdateTests(TransactionTestCase):
         Test that the backend's FOR UPDATE NOWAIT variant appears in
         generated SQL when select_for_update is invoked.
         """
-        list(Person.objects.all().select_for_update(nowait=True))
+        with transaction.atomic():
+            list(Person.objects.all().select_for_update(nowait=True))
         self.assertTrue(self.has_for_update_sql(connection, nowait=True))
 
     @requires_threading
@@ -125,6 +127,26 @@ class SelectForUpdateTests(TransactionTestCase):
             Person.objects.all().select_for_update(nowait=True)
         )
 
+    @skipUnlessDBFeature('has_select_for_update')
+    def test_for_update_requires_transaction(self):
+        """
+        Test that a TransactionManagementError is raised
+        when a select_for_update query is executed outside of a transaction.
+        """
+        with self.assertRaises(transaction.TransactionManagementError):
+            list(Person.objects.all().select_for_update())
+
+    @skipUnlessDBFeature('has_select_for_update')
+    def test_for_update_requires_transaction_only_in_execution(self):
+        """
+        Test that no TransactionManagementError is raised
+        when select_for_update is invoked outside of a transaction -
+        only when the query is executed.
+        """
+        people = Person.objects.all().select_for_update()
+        with self.assertRaises(transaction.TransactionManagementError):
+            list(people)
+
     def run_select_for_update(self, status, nowait=False):
         """
         Utility method that runs a SELECT FOR UPDATE against all