move supports_async to DatabaseFeatures class.

django/db/__init__.py

@@ -51,7 +51,7 @@ class new_connection:
 
     async def __aenter__(self):
         conn = connections.create_connection(self.using)
-        if conn.supports_async is False:
+        if conn.features.supports_async is False:
             raise NotSupportedError(
                 "The database backend does not support asynchronous execution."
             )

django/db/backends/base/base.py

@@ -39,7 +39,6 @@ class BaseDatabaseWrapper:
     ops = None
     vendor = "unknown"
     display_name = "unknown"
-    supports_async = False
 
     SchemaEditorClass = None
     # Classes instantiated in __init__().

django/db/backends/base/features.py

@@ -353,6 +353,9 @@ class BaseDatabaseFeatures:
     # Does the backend support negative JSON array indexing?
     supports_json_negative_indexing = True
 
+    # Asynchronous database operations
+    supports_async = False
+
     # Does the backend support column collations?
     supports_collation_on_charfield = True
     supports_collation_on_textfield = True

django/db/backends/postgresql/base.py

@@ -93,7 +93,6 @@ class DatabaseWrapper(BaseDatabaseWrapper):
     vendor = "postgresql"
     display_name = "PostgreSQL"
     _pg_version = None
-    supports_async = is_psycopg3
 
     # This dictionary maps Field objects to their associated PostgreSQL column
     # types, as strings. Column-type strings can contain format strings; they'll

django/db/backends/postgresql/features.py

@@ -53,6 +53,7 @@ class DatabaseFeatures(BaseDatabaseFeatures):
         END;
     $$ LANGUAGE plpgsql;"""
     requires_casted_case_in_updates = True
+    supports_async = is_psycopg3
     supports_over_clause = True
     supports_frame_exclusion = True
     only_supports_unbounded_with_preceding_and_following = True

django/db/backends/utils.py

@@ -319,7 +319,7 @@ def debug_transaction(connection, sql):
                 {
                     "sql": "%s" % sql,
                     "time": "%.3f" % duration,
-                    "async": connection.supports_async,
+                    "async": connection.features.supports_async,
                 }
             )
             logger.debug(
@@ -328,12 +328,12 @@ def debug_transaction(connection, sql):
                 sql,
                 None,
                 connection.alias,
-                connection.supports_async,
+                connection.features.supports_async,
                 extra={
                     "duration": duration,
                     "sql": sql,
                     "alias": connection.alias,
-                    "async": connection.supports_async,
+                    "async": connection.features.supports_async,
                 },
             )
 

tests/async/test_async_connections.py

@@ -1,14 +1,12 @@
-import unittest
-
 from asgiref.sync import sync_to_async
 
-from django.db import connection, new_connection
-from django.test import TransactionTestCase
+from django.db import new_connection
+from django.test import TransactionTestCase, skipUnlessDBFeature
 
 from .models import SimpleModel
 
 
-@unittest.skipUnless(connection.supports_async is True, "Async DB test")
+@skipUnlessDBFeature("supports_async")
 class AsyncSyncCominglingTest(TransactionTestCase):
 
     available_apps = ["async"]

tests/async/test_async_cursor.py

@@ -1,11 +1,11 @@
-import unittest
-
-from django.db import connection, new_connection
-from django.test import SimpleTestCase
+from django.db import new_connection
+from django.test import SimpleTestCase, skipUnlessDBFeature
 
 
-@unittest.skipUnless(connection.supports_async is True, "Async DB test")
+@skipUnlessDBFeature("supports_async")
 class AsyncCursorTests(SimpleTestCase):
+    databases = {"default", "other"}
+
     async def test_aexecute(self):
         async with new_connection() as conn:
             async with conn.acursor() as cursor:

tests/backends/base/test_base_async.py

@@ -1,11 +1,11 @@
-import unittest
-
-from django.db import connection, new_connection
-from django.test import SimpleTestCase
+from django.db import new_connection
+from django.test import SimpleTestCase, skipUnlessDBFeature
 
 
-@unittest.skipUnless(connection.supports_async is True, "Async DB test")
+@skipUnlessDBFeature("supports_async")
 class AsyncDatabaseWrapperTests(SimpleTestCase):
+    databases = {"default", "other"}
+
     async def test_async_cursor(self):
         async with new_connection() as conn:
             async with conn.acursor() as cursor:

tests/db_utils/tests.py

@@ -20,7 +20,7 @@ from django.db.utils import (
     ConnectionHandler,
     load_backend,
 )
-from django.test import SimpleTestCase, TestCase
+from django.test import SimpleTestCase, TestCase, skipUnlessDBFeature
 from django.utils.connection import ConnectionDoesNotExist
 
 
@@ -108,6 +108,8 @@ class LoadBackendTests(SimpleTestCase):
 
 
 class AsyncConnectionTests(SimpleTestCase):
+    databases = {"default", "other"}
+
     def run_pool(self, coro, count=2):
         def fn():
             asyncio.run(coro())
@@ -146,7 +148,7 @@ class AsyncConnectionTests(SimpleTestCase):
 
         self.run_pool(coro)
 
-    @unittest.skipUnless(connection.supports_async is True, "Async DB test")
+    @skipUnlessDBFeature("supports_async")
     def test_new_connection_threading(self):
         async def coro():
             assert async_connections.empty is True
@@ -156,7 +158,7 @@ class AsyncConnectionTests(SimpleTestCase):
 
         self.run_pool(coro)
 
-    @unittest.skipUnless(connection.supports_async is True, "Async DB test")
+    @skipUnlessDBFeature("supports_async")
     async def test_new_connection(self):
         with self.assertRaises(ConnectionDoesNotExist):
             async_connections.get_connection(DEFAULT_DB_ALIAS)
@@ -177,7 +179,7 @@ class AsyncConnectionTests(SimpleTestCase):
         with self.assertRaises(ConnectionDoesNotExist):
             async_connections.get_connection(DEFAULT_DB_ALIAS)
 
-    @unittest.skipUnless(connection.supports_async is False, "Sync DB test")
+    @skipUnlessDBFeature("supports_async")
     async def test_new_connection_on_sync(self):
         with self.assertRaises(NotSupportedError):
             async with new_connection():

tests/transactions/tests.py

@@ -580,8 +580,7 @@ class DurableTests(DurableTestsBase, TestCase):
     pass
 
 
-@skipUnlessDBFeature("uses_savepoints")
-@skipUnless(connection.supports_async is True, "Async DB test")
+@skipUnlessDBFeature("uses_savepoints", "supports_async")
 class AsyncTransactionTestCase(TransactionTestCase):
     available_apps = ["transactions"]