Refs #27236 -- Added generic mechanism to handle the deprecation of migration operations.

tests/postgres_tests/migrations/0001_setup_extensions.py

@@ -1,6 +1,17 @@
-from unittest import mock
-
 from django.db import connection, migrations
+from django.db.migrations.operations.base import Operation
+
+
+class DummyOperation(Operation):
+    def state_forwards(self, app_label, state):
+        pass
+
+    def database_forwards(self, app_label, schema_editor, from_state, to_state):
+        pass
+
+    def database_backwards(self, app_label, schema_editor, from_state, to_state):
+        pass
+
 
 try:
     from django.contrib.postgres.operations import (
@@ -15,14 +26,14 @@ try:
         UnaccentExtension,
     )
 except ImportError:
-    BloomExtension = mock.Mock()
-    BtreeGinExtension = mock.Mock()
-    BtreeGistExtension = mock.Mock()
-    CITextExtension = mock.Mock()
-    CreateExtension = mock.Mock()
-    HStoreExtension = mock.Mock()
-    TrigramExtension = mock.Mock()
-    UnaccentExtension = mock.Mock()
+    BloomExtension = DummyOperation
+    BtreeGinExtension = DummyOperation
+    BtreeGistExtension = DummyOperation
+    CITextExtension = DummyOperation
+    CreateExtension = DummyOperation
+    HStoreExtension = DummyOperation
+    TrigramExtension = DummyOperation
+    UnaccentExtension = DummyOperation
     needs_crypto_extension = False
 else:
     needs_crypto_extension = (
@@ -41,7 +52,7 @@ class Migration(migrations.Migration):
         # dash in its name.
         CreateExtension("uuid-ossp"),
         # CryptoExtension is required for RandomUUID() on PostgreSQL < 13.
-        CryptoExtension() if needs_crypto_extension else mock.Mock(),
+        CryptoExtension() if needs_crypto_extension else DummyOperation(),
         HStoreExtension(),
         TrigramExtension(),
         UnaccentExtension(),