From 05ea4fd37df97d47e8959f0c3b0fbc37816a2033 Mon Sep 17 00:00:00 2001
From: mengjincn <mengjincn@163.com>
Date: Wed, 29 Nov 2023 04:49:56 +0800
Subject: [PATCH] fix merge None value and non None value error (#13703)

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---
 libs/core/langchain_core/messages/base.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libs/core/langchain_core/messages/base.py b/libs/core/langchain_core/messages/base.py
index c790972725..1c2f97a139 100644
--- a/libs/core/langchain_core/messages/base.py
+++ b/libs/core/langchain_core/messages/base.py
@@ -76,6 +76,8 @@ class BaseMessageChunk(BaseMessage):
         for k, v in right.items():
             if k not in merged:
                 merged[k] = v
+            elif merged[k] is None and v:
+                merged[k] = v
             elif type(merged[k]) != type(v):
                 raise ValueError(
                     f'additional_kwargs["{k}"] already exists in this message,'