fix: close content part before tool calls to prevent no-start-event error (#786)

Author: maxduu

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "uipath-langchain"
-version = "0.9.32"
+version = "0.9.33"
 description = "Python SDK that enables developers to build and deploy LangGraph agents to the UiPath Cloud Platform"
 readme = { file = "README.md", content-type = "text/markdown" }
 requires-python = ">=3.11"

src/uipath_langchain/runtime/messages.py

@@ -355,6 +355,7 @@ async def map_ai_message_chunk_to_events(
                 events.append(self._chunk_to_message_event(message.id, chunk))
             self._citation_stream_processor = CitationStreamProcessor()
 
+            events.append(self.map_to_content_part_end_event(message.id))
             if (
                 self.current_message.tool_calls is not None
                 and len(self.current_message.tool_calls) > 0
@@ -389,6 +390,7 @@ async def map_ai_message_to_events(
                 events.append(self._chunk_to_message_event(message.id, chunk))
             self._citation_stream_processor = CitationStreamProcessor()
 
+        events.append(self.map_to_content_part_end_event(message.id))
         if message.tool_calls:
             events.extend(await self.map_current_message_to_start_tool_call_events())
         else:
@@ -578,6 +580,13 @@ def map_to_message_end_event(
         return UiPathConversationMessageEvent(
             message_id=message_id,
             end=UiPathConversationMessageEndEvent(),
+        )
+
+    def map_to_content_part_end_event(
+        self, message_id: str
+    ) -> UiPathConversationMessageEvent:
+        return UiPathConversationMessageEvent(
+            message_id=message_id,
             content_part=UiPathConversationContentPartEvent(
                 content_part_id=self.get_content_part_id(message_id),
                 end=UiPathConversationContentPartEndEvent(),

tests/runtime/test_chat_message_mapper.py

@@ -1136,11 +1136,15 @@ async def test_map_event_emits_end_event_for_last_chunk_without_tool_calls(self)
         result = await mapper.map_event(last_chunk)
 
         assert result is not None
-        # Should have the end event
+        # Should have content part end event followed by message end event
+        content_part_end_event = result[-2]
+        assert content_part_end_event.content_part is not None
+        assert content_part_end_event.content_part.end is not None
+        assert content_part_end_event.end is None
+
         end_event = result[-1]
         assert end_event.end is not None
-        assert end_event.content_part is not None
-        assert end_event.content_part.end is not None
+        assert end_event.content_part is None
 
     @pytest.mark.asyncio
     async def test_map_event_emits_tool_call_start_events_on_last_chunk(self):
@@ -1771,10 +1775,14 @@ async def test_emits_start_and_end_events(self):
         assert start_event.content_part is not None
         assert start_event.content_part.start is not None
 
+        content_part_end_event = result[-2]
+        assert content_part_end_event.content_part is not None
+        assert content_part_end_event.content_part.end is not None
+        assert content_part_end_event.end is None
+
         end_event = result[-1]
         assert end_event.end is not None
-        assert end_event.content_part is not None
-        assert end_event.content_part.end is not None
+        assert end_event.content_part is None
 
     @pytest.mark.asyncio
     async def test_emits_content_chunk_for_string_content(self):