refactor: unify subscription deletion transactions

tests/test_subscribe_interaction_delete.py

@@ -0,0 +1,52 @@
+"""订阅消息交互删除动作的应用边界测试。"""
+
+from types import SimpleNamespace
+
+from app.application.messaging.subscribe import SubscribeInteractionHandler
+
+
+class _Repository:
+    """只提供消息展示所需读取能力的订阅仓储替身。"""
+
+    def __init__(self, subscribes):
+        """按订阅 ID 保存测试快照。"""
+        self._subscribes = subscribes
+
+    def get(self, subscribe_id):
+        """返回指定订阅快照。"""
+        return self._subscribes.get(subscribe_id)
+
+
+def test_interaction_delete_delegates_each_existing_id_to_application_action():
+    """消息层只负责解析和展示，删除必须委托统一 Application 动作。"""
+    deleted_ids = []
+    handler = SubscribeInteractionHandler(
+        messenger=SimpleNamespace(),
+        actions=SimpleNamespace(),
+        repository=_Repository({
+            7: SimpleNamespace(name="电影订阅"),
+            8: SimpleNamespace(name="剧集订阅"),
+        }),
+        delete_subscription=lambda subscribe_id: deleted_ids.append(subscribe_id) or True,
+    )
+
+    success, message = handler._delete_subscribes("7 8 9")
+
+    assert success is True
+    assert deleted_ids == [7, 8]
+    assert message == "已删除 2 个订阅：电影订阅, 剧集订阅；未找到：9"
+
+
+def test_interaction_delete_reports_transaction_race_as_missing():
+    """读取后事务内目标消失时不得误报已删除。"""
+    handler = SubscribeInteractionHandler(
+        messenger=SimpleNamespace(),
+        actions=SimpleNamespace(),
+        repository=_Repository({7: SimpleNamespace(name="电影订阅")}),
+        delete_subscription=lambda _subscribe_id: False,
+    )
+
+    success, message = handler._delete_subscribes("7")
+
+    assert success is False
+    assert message == "未找到订阅：7"