test(sqlserver): add testsuite basic/ddl ALTER TABLE bridge tests and provider get_dialect

Author: vistart

tests/providers/basic.py

@@ -341,6 +341,17 @@ def get_test_scenarios(self) -> List[str]:
     def get_yes_no_adapter(self) -> "BaseSQLTypeAdapter":
         return YesOrNoBooleanAdapter()
 
+    def get_dialect(self, scenario_name: str = "default"):
+        """Return a bare, fully-constructed SQL Server dialect instance.
+
+        Used by the ``feature/basic/ddl`` subtopic (expression/dialect
+        contract). ``(16, 0, 0)`` advertises support for the ``IF
+        [NOT] EXISTS`` ``DROP`` modifiers (available since 2016).
+        """
+        from rhosocial.activerecord.backend.impl.sqlserver.dialect import SQLServerDialect
+
+        return SQLServerDialect(version=(16, 0, 0))
+
     def _track_backend(self, backend_instance, collection: List) -> None:
         if backend_instance not in collection:
             collection.append(backend_instance)
@@ -544,6 +555,10 @@ def __init__(self):
         super().__init__()
         self._active_async_backends = []
 
+    async def get_dialect(self, scenario_name: str = "default"):
+        """Async mirror of ``BasicProviderBase.get_dialect``."""
+        return super().get_dialect(scenario_name)
+
     async def _setup_async_model(
         self, model_class: Type[ActiveRecord], scenario_name: str, table_name: str
     ) -> Type[ActiveRecord]:

tests/rhosocial/activerecord_sqlserver_test/feature/basic/ddl/conftest.py

@@ -0,0 +1,10 @@
+# tests/rhosocial/activerecord_sqlserver_test/feature/basic/ddl/conftest.py
+"""
+Pytest configuration for the basic/ddl ALTER TABLE tests.
+
+This file imports fixtures from the corresponding testsuite subtopic, making
+them (and the ``requires_protocol`` protocol-check autouse fixture) available
+to the tests in this directory.
+"""
+
+from rhosocial.activerecord.testsuite.feature.basic.ddl.conftest import *  # noqa: F403

tests/rhosocial/activerecord_sqlserver_test/feature/basic/ddl/test_alter_table_if_exists.py

@@ -0,0 +1,10 @@
+# tests/rhosocial/activerecord_sqlserver_test/feature/basic/ddl/test_alter_table_if_exists.py
+"""
+ALTER TABLE IF [NOT] EXISTS tests (sync) for the SQL Server backend.
+
+Thin bridge that runs the shared testsuite contract against the SQL Server
+dialect, which supports ``DROP COLUMN IF EXISTS`` / ``DROP CONSTRAINT
+IF EXISTS`` (2016+) but not ``ADD COLUMN IF NOT EXISTS``.
+"""
+
+from rhosocial.activerecord.testsuite.feature.basic.ddl.test_alter_table_if_exists import *  # noqa: F403

tests/rhosocial/activerecord_sqlserver_test/feature/basic/ddl/test_alter_table_if_exists_async.py

@@ -0,0 +1,8 @@
+# tests/rhosocial/activerecord_sqlserver_test/feature/basic/ddl/test_alter_table_if_exists_async.py
+"""
+ALTER TABLE IF [NOT] EXISTS tests (async) for the SQL Server backend.
+
+Async mirror of ``test_alter_table_if_exists.py``.
+"""
+
+from rhosocial.activerecord.testsuite.feature.basic.ddl.test_alter_table_if_exists_async import *  # noqa: E501, F401, F403