fix(feishu): handle _resuming in send_delta to prevent duplicate messages (#2667)

When a tool call triggers a mid-turn _stream_end(resuming=True), Feishu
channel unconditionally popped the buffer and closed the streaming card.
The next segment then created a new card, causing duplicate/fragmented
replies.

Now send_delta checks _resuming: if True, it flushes current text to
the existing card but keeps the buffer alive so subsequent segments
append to the same card. Only the final _stream_end (resuming=False)
pops the buffer and closes streaming mode.


Made-with: Cursor

nanobot/channels/feishu.py

@@ -1046,6 +1046,19 @@ class FeishuChannel(BaseChannel):
 
         # --- stream end: final update or fallback ---
         if meta.get("_stream_end"):
+            resuming = meta.get("_resuming", False)
+            if resuming:
+                # Mid-turn pause (e.g. tool call between streaming segments).
+                # Flush current text to card but keep the buffer alive so the
+                # next segment appends to the same card.
+                buf = self._stream_bufs.get(chat_id)
+                if buf and buf.card_id and buf.text:
+                    buf.sequence += 1
+                    await loop.run_in_executor(
+                        None, self._stream_update_text_sync, buf.card_id, buf.text, buf.sequence,
+                    )
+                return
+
             buf = self._stream_bufs.pop(chat_id, None)
             if not buf or not buf.text:
                 return

tests/channels/test_feishu_streaming.py

@@ -203,6 +203,55 @@ class TestSendDelta:
         ch._client.cardkit.v1.card_element.content.assert_not_called()
         ch._client.im.v1.message.create.assert_called_once()
 
+    @pytest.mark.asyncio
+    async def test_stream_end_resuming_keeps_buffer(self):
+        """_resuming=True flushes text to card but keeps the buffer for the next segment."""
+        ch = _make_channel()
+        ch._stream_bufs["oc_chat1"] = _FeishuStreamBuf(
+            text="Partial answer", card_id="card_1", sequence=2, last_edit=0.0,
+        )
+        ch._client.cardkit.v1.card_element.content.return_value = _mock_content_response()
+
+        await ch.send_delta("oc_chat1", "", metadata={"_stream_end": True, "_resuming": True})
+
+        assert "oc_chat1" in ch._stream_bufs
+        buf = ch._stream_bufs["oc_chat1"]
+        assert buf.card_id == "card_1"
+        assert buf.sequence == 3
+        ch._client.cardkit.v1.card_element.content.assert_called_once()
+        ch._client.cardkit.v1.card.settings.assert_not_called()
+
+    @pytest.mark.asyncio
+    async def test_stream_end_resuming_then_final_end(self):
+        """Full multi-segment flow: resuming mid-turn, then final end closes the card."""
+        ch = _make_channel()
+        ch._stream_bufs["oc_chat1"] = _FeishuStreamBuf(
+            text="Seg1", card_id="card_1", sequence=1, last_edit=0.0,
+        )
+        ch._client.cardkit.v1.card_element.content.return_value = _mock_content_response()
+        ch._client.cardkit.v1.card.settings.return_value = _mock_content_response()
+
+        await ch.send_delta("oc_chat1", "", metadata={"_stream_end": True, "_resuming": True})
+        assert "oc_chat1" in ch._stream_bufs
+
+        ch._stream_bufs["oc_chat1"].text += " Seg2"
+        await ch.send_delta("oc_chat1", "", metadata={"_stream_end": True})
+
+        assert "oc_chat1" not in ch._stream_bufs
+        ch._client.cardkit.v1.card.settings.assert_called_once()
+
+    @pytest.mark.asyncio
+    async def test_stream_end_resuming_no_card_is_noop(self):
+        """_resuming with no card_id (card creation failed) is a safe no-op."""
+        ch = _make_channel()
+        ch._stream_bufs["oc_chat1"] = _FeishuStreamBuf(
+            text="text", card_id=None, sequence=0, last_edit=0.0,
+        )
+        await ch.send_delta("oc_chat1", "", metadata={"_stream_end": True, "_resuming": True})
+
+        assert "oc_chat1" in ch._stream_bufs
+        ch._client.cardkit.v1.card_element.content.assert_not_called()
+
     @pytest.mark.asyncio
     async def test_stream_end_without_buf_is_noop(self):
         ch = _make_channel()