Fixed #36663 -- Defaulted to running checks against all databases.

Regression in 0b83c8cc4db95812f1e15ca19d78614e94cf38dd which added
support for running checks only against databases but also defaulted to
running against no databases if not specified.

Note that this continues to *not* default to runing database tagged
checks for all management commands except the migrate one as whether or
not we should change this must be discussed further.

Thanks Tim Graham for surfacing how this was a problematic default.

1 files changed, 30 insertions, 7 deletions

diff --git a/tests/check_framework/tests.py b/tests/check_framework/tests.py
index c5f53c4789..138d27aafd 100644
--- a/tests/check_framework/tests.py
+++ b/tests/check_framework/tests.py
@@ -92,6 +92,21 @@ class SystemCheckFrameworkTests(SimpleTestCase):
         with self.assertRaisesMessage(TypeError, msg):
             registry.run_checks()
 
+    def test_run_checks_database_exclusion(self):
+        registry = CheckRegistry()
+
+        database_errors = [checks.Warning("Database Check")]
+
+        @registry.register(Tags.database)
+        def database_system_check(**kwargs):
+            return database_errors
+
+        errors = registry.run_checks()
+        self.assertEqual(errors, [])
+
+        errors = registry.run_checks(databases=["default"])
+        self.assertEqual(errors, database_errors)
+
 
 class MessageTests(SimpleTestCase):
     def test_printing(self):
@@ -190,10 +205,12 @@ class CheckCommandTests(SimpleTestCase):
     def test_simple_call(self):
         call_command("check")
         self.assertEqual(
-            simple_system_check.kwargs, {"app_configs": None, "databases": None}
+            simple_system_check.kwargs,
+            {"app_configs": None, "databases": ["default", "other"]},
         )
         self.assertEqual(
-            tagged_system_check.kwargs, {"app_configs": None, "databases": None}
+            tagged_system_check.kwargs,
+            {"app_configs": None, "databases": ["default", "other"]},
         )
 
     @override_system_checks([simple_system_check, tagged_system_check])
@@ -203,11 +220,17 @@ class CheckCommandTests(SimpleTestCase):
         admin_config = apps.get_app_config("admin")
         self.assertEqual(
             simple_system_check.kwargs,
-            {"app_configs": [auth_config, admin_config], "databases": None},
+            {
+                "app_configs": [auth_config, admin_config],
+                "databases": ["default", "other"],
+            },
         )
         self.assertEqual(
             tagged_system_check.kwargs,
-            {"app_configs": [auth_config, admin_config], "databases": None},
+            {
+                "app_configs": [auth_config, admin_config],
+                "databases": ["default", "other"],
+            },
         )
 
     @override_system_checks([simple_system_check, tagged_system_check])
@@ -215,7 +238,8 @@ class CheckCommandTests(SimpleTestCase):
         call_command("check", tags=["simpletag"])
         self.assertIsNone(simple_system_check.kwargs)
         self.assertEqual(
-            tagged_system_check.kwargs, {"app_configs": None, "databases": None}
+            tagged_system_check.kwargs,
+            {"app_configs": None, "databases": ["default", "other"]},
         )
 
     @override_system_checks([simple_system_check, tagged_system_check])
@@ -273,8 +297,7 @@ class CheckCommandTests(SimpleTestCase):
 
         with override_system_checks([database_check]):
             call_command("check")
-            database_check.assert_called_once_with(app_configs=None, databases=None)
-            database_check.reset_mock()
+            database_check.assert_not_called()
             call_command("check", databases=["default"])
             database_check.assert_called_once_with(
                 app_configs=None, databases=["default"]