test: fix test_ai_tasks + format cover.py for #1341

apps/api/app/api/routes/templates_editor/cover.py

@@ -125,6 +125,7 @@ def editor_generate_cover(
             primary_video_url = rendered_storage_key
         else:
             from packages.shared.storage import get_shared_storage_service
+
             storage_svc = get_shared_storage_service()
             primary_video_url = storage_svc.get_url(rendered_storage_key)
         logger.info(

tests/unit/test_ai_tasks.py

@@ -399,18 +399,16 @@ class TestRunAIRecommend(unittest.TestCase):
 
 
 class TestGenerateCover(unittest.TestCase):
-    """封面生成测试（降级路径）."""
+    """封面生成测试."""
 
-    def test_ai_frame_type(self):
-        """AI封面模式返回预期结构."""
-        result = run_generate_cover(
-            plan_id="plan-1",
-            asset_ids=["a1"],
-            cover_type="ai_frame",
-        )
-        self.assertIn("type", result)
-        self.assertEqual(result["type"], "ai_frame")
-        self.assertIn("image_url", result)
+    def test_ai_frame_type_raises_without_mediakit(self):
+        """AI封面模式在MediaKit不可用时抛出RuntimeError."""
+        with self.assertRaises(RuntimeError):
+            run_generate_cover(
+                plan_id="plan-1",
+                asset_ids=["a1"],
+                cover_type="ai_frame",
+            )
 
     def test_manual_type(self):
         """手动选帧模式."""