feat(governance): unify durable event retention

tests/test_cleanup_index_migration.py

@@ -0,0 +1,75 @@
+"""历史表清理索引迁移测试。"""
+
+import importlib
+
+import sqlalchemy as sa
+from alembic.migration import MigrationContext
+from alembic.operations import Operations
+
+
+MIGRATION_MODULE = "database.versions.a6c8e2f4b1d3_3_0_11"
+INDEXES = {
+    "subscribehistory": (
+        "ix_subscribehistory_date_id",
+        ("date", "id"),
+    ),
+    "agentchat": (
+        "ix_agentchat_updated_id",
+        ("updated_at", "id"),
+    ),
+    "agenttaskrun": (
+        "ix_agenttaskrun_status_started_id",
+        ("status", "started_at", "id"),
+    ),
+}
+
+
+def _index_columns(connection, table_name: str) -> dict[str, tuple[str, ...]]:
+    """返回测试表的索引字段签名。"""
+    return {
+        index["name"]: tuple(index.get("column_names") or ())
+        for index in sa.inspect(connection).get_indexes(table_name)
+    }
+
+
+def test_cleanup_index_migration_is_idempotent_and_reversible(monkeypatch) -> None:
+    """升级可重复执行并创建准确索引，降级只移除新增索引。"""
+    engine = sa.create_engine("sqlite://")
+    metadata = sa.MetaData()
+    sa.Table(
+        "subscribehistory",
+        metadata,
+        sa.Column("id", sa.Integer(), primary_key=True),
+        sa.Column("date", sa.String()),
+    )
+    sa.Table(
+        "agentchat",
+        metadata,
+        sa.Column("id", sa.Integer(), primary_key=True),
+        sa.Column("updated_at", sa.String()),
+    )
+    sa.Table(
+        "agenttaskrun",
+        metadata,
+        sa.Column("id", sa.Integer(), primary_key=True),
+        sa.Column("status", sa.String()),
+        sa.Column("started_at", sa.String()),
+    )
+
+    with engine.begin() as connection:
+        metadata.create_all(connection)
+        migration = importlib.import_module(MIGRATION_MODULE)
+        monkeypatch.setattr(
+            migration,
+            "op",
+            Operations(MigrationContext.configure(connection)),
+        )
+
+        migration.upgrade()
+        migration.upgrade()
+        for table_name, (index_name, columns) in INDEXES.items():
+            assert _index_columns(connection, table_name)[index_name] == columns
+
+        migration.downgrade()
+        for table_name, (index_name, _columns) in INDEXES.items():
+            assert index_name not in _index_columns(connection, table_name)