Force ordering of settings and transactional_db fixtures #870

Author: bdauvergne

pytest_django/fixtures.py

@@ -431,10 +431,16 @@ def finalize(self) -> None:
 
 
 @pytest.fixture()
-def settings():
+def settings(request):
     """A Django settings object which restores changes after the testrun"""
     skip_if_no_django()
 
+    # Order the `settings` fixture after DB.
+    # We don't want overridden settings to be in effect during
+    # DB setup/teardown/post_migrate.
+    if 'transactional_db' in request.fixturenames:
+        request.getfixturevalue('transactional_db')
+
     wrapper = SettingsWrapper()
     yield wrapper
     wrapper.finalize()

tests/test_fixtures.py

@@ -408,6 +408,30 @@ def test_set_non_existent(settings):
             ]
         )
 
+    def test_transactional_db_order(self, django_testdir):
+        django_testdir.create_test_module(
+            """
+            import pytest
+
+            from django.conf import settings as django_settings
+            from django.db.models.signals import post_migrate
+
+            @pytest.fixture
+            def check_settings_in_post_migrate(settings, transactional_db):
+                def receiver(sender, **kwargs):
+                    assert not hasattr(django_settings, 'TRANSIENT_SETTING')
+
+                post_migrate.connect(receiver, weak=False)
+
+            def test_set_non_existent(settings, check_settings_in_post_migrate):
+                settings.TRANSIENT_SETTING = 1
+         """
+        )
+
+        result = django_testdir.runpytest_subprocess("-v")
+        assert result.ret == 0
+        result.stdout.fnmatch_lines(["*test_set_non_existent PASSED*"])
+
 
 class TestLiveServer:
     def test_settings_before(self) -> None: