fix fk migrate

tests/backends/mysql/test_migrate.py

@@ -1,6 +1,17 @@
-from tests.backends.mysql import DBTestCase
+from asynctest import TestCase
+from tortoise import Tortoise
+
+from alice.migrate import Migrate
+from tests.backends.mysql import TORTOISE_ORM
 
 
-class TestMigrate(DBTestCase):
+class TestMigrate(TestCase):
+    async def setUp(self) -> None:
+        await Migrate.init_with_old_models(TORTOISE_ORM, "models", "./migrations")
+
     async def test_migrate(self):
-        pass
+        Migrate.diff_model(
+            Tortoise.apps.get("models").get("Category"),
+            Tortoise.apps.get("diff_models").get("Category"),
+        )
+        print(Migrate.upgrade_operators)