From 927ab77d6e839d7e12aaab00faa9b527afa4a214 Mon Sep 17 00:00:00 2001
From: Erick Friis <erick@langchain.dev>
Date: Wed, 7 Feb 2024 17:14:50 -0800
Subject: [PATCH] google-genai[patch]: no error for FunctionMessage (#17215)

Both should eventually match this:
https://github.com/langchain-ai/langchain/blob/master/libs/partners/google-vertexai/langchain_google_vertexai/chat_models.py#L179

But seems undocumented / can't find types in genai package
---
 .../google-genai/langchain_google_genai/chat_models.py   | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/libs/partners/google-genai/langchain_google_genai/chat_models.py b/libs/partners/google-genai/langchain_google_genai/chat_models.py
index 2bf9cf8cc3d..2f0d35428d5 100644
--- a/libs/partners/google-genai/langchain_google_genai/chat_models.py
+++ b/libs/partners/google-genai/langchain_google_genai/chat_models.py
@@ -39,6 +39,7 @@ from langchain_core.messages import (
     BaseMessage,
     ChatMessage,
     ChatMessageChunk,
+    FunctionMessage,
     HumanMessage,
     HumanMessageChunk,
     SystemMessage,
@@ -326,14 +327,20 @@ llm = ChatGoogleGenerativeAI(model="gemini-pro", convert_system_message_to_human
             continue
         elif isinstance(message, AIMessage):
             role = "model"
+            # TODO: Handle AImessage with function call
+            parts = _convert_to_parts(message.content)
         elif isinstance(message, HumanMessage):
             role = "user"
+            parts = _convert_to_parts(message.content)
+        elif isinstance(message, FunctionMessage):
+            role = "user"
+            # TODO: Handle FunctionMessage
+            parts = _convert_to_parts(message.content)
         else:
             raise ValueError(
                 f"Unexpected message with type {type(message)} at the position {i}."
             )
 
-        parts = _convert_to_parts(message.content)
         if raw_system_message:
             if role == "model":
                 raise ValueError(