fix(lark): admit topic events with absent optional ancestry (#6011)

Signed-off-by: LoopX Agent <337587101+loopx-agent@users.noreply.github.com>

Author: loopx-agent

loopx/extensions/lark/private_conversations.py

@@ -112,9 +112,17 @@ def _source_message(self, record: dict[str, Any], *, selected: dict[str, Any] |
                 if selected["binding"].get("audience") == "group":
                     # Provider readback, never event text, fixes the topic root.
                     root = str(message.get("root_id") or message["message_id"])
+                    # The compact event projection emits null for absent
+                    # ancestry. mget can enrich the thread id later; that is
+                    # not a conflict unless the event supplied another id.
+                    # Parent/root ancestry must still agree exactly.
+                    parent = str(message.get("parent_id") or "")
+                    event_parent = str(event.get("parent_id") or "")
+                    event_thread = str(event.get("thread_id") or "")
                     if (root != str(event.get("root_id") or event["message_id"])
-                            or (message.get("parent_id") and not message.get("root_id"))
-                            or any(message.get(key, "") != event.get(key, "") for key in ["parent_id", "thread_id"])):
+                            or (parent and not message.get("root_id"))
+                            or parent != event_parent
+                            or (event_thread and event_thread != str(message.get("thread_id") or ""))):
                         return None
                     if root == event["message_id"]:
                         original: Mapping[str, Any] | None = message

tests/test_lark_private_conversations.py

@@ -328,6 +328,42 @@ def test_group_provider_mention_survives_a_bot_rename_and_topic_followup(ordinar
         runtime.close()
 
 
+@pytest.mark.parametrize("is_reply", [False, True])
+def test_group_readback_accepts_null_event_fields_and_provider_enriched_thread(ordinary, is_reply):  # noqa: F811
+    _, runtime, provider, transport = connect_group(ordinary)
+    try:
+        root = provider.topic("compact-topic", "Explain this project")
+        # The CLI event projection emits null for absent fields; mget can
+        # supply the topic's thread id even when the event did not carry it.
+        root.update(root_id=None, parent_id=None, thread_id=None)
+        provider.messages[root["message_id"]]["thread_id"] = "omt_compact_topic"
+        provider.messages[root["message_id"]]["mentions"] = [{"id": "cli_notes_app", "name": "notes-app"}]
+        event = root
+        if is_reply:
+            event = provider.topic("compact-reply", "Compare its configuration", root=root["message_id"])
+            event["thread_id"] = None
+            provider.messages[event["message_id"]]["thread_id"] = "omt_compact_topic"
+        assert transport.admit("notes-app", event)["status"] == "durably_accepted"
+        finish_group_turn(runtime, transport, message=event["content"])
+        assert all(topic == root["message_id"] for _, topic, _ in provider.topic_writes)
+    finally:
+        runtime.close()
+
+
+@pytest.mark.parametrize("field,value", [("parent_id", "om_wrong_parent"), ("thread_id", "omt_wrong_thread")])
+def test_group_readback_rejects_supplied_conflicting_ancestry(ordinary, field, value):  # noqa: F811
+    store, runtime, provider, transport = connect_group(ordinary)
+    try:
+        root = provider.topic("conflicting-topic", "Explain this project")
+        event = provider.topic("conflicting-reply", "Continue", root=root["message_id"])
+        event[field] = value
+        assert transport.admit("notes-app", event)["status"] == "source_verification_failed"
+        assert not store.list_sessions() and not list(transport.root.glob("*.json"))
+        assert provider.writes == []
+    finally:
+        runtime.close()
+
+
 def test_group_status_and_recipient_commands_cannot_expose_private_sessions(ordinary):  # noqa: F811
     store, runtime, provider, transport = connect_group(ordinary)
     try: