Uncaught TypeError in base_coder.py line 675

[GodgunPk]

Aider version: 0.86.2
Python version: 3.12.8
Platform: Linux-6.12.100+deb13-amd64-x86_64-with-glibc2.41
Python implementation: CPython
Virtual environment: Yes
OS: Linux 6.12.100+deb13-amd64 (64bit)
Git version: git version 2.47.3

An uncaught exception occurred:

Traceback (most recent call last):
  File "aider", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "main.py", line 1162, in main
    coder.run()
  File "base_coder.py", line 887, in run
    self.run_one(user_message, preproc)
  File "base_coder.py", line 934, in run_one
    list(self.send_message(message))
  File "base_coder.py", line 1429, in send_message
    chunks = self.format_messages()
             ^^^^^^^^^^^^^^^^^^^^^^
  File "base_coder.py", line 1334, in format_messages
    chunks = self.format_chat_chunks()
             ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "base_coder.py", line 1281, in format_chat_chunks
    chunks.repo = self.get_repo_messages()
                  ^^^^^^^^^^^^^^^^^^^^^^^^
  File "base_coder.py", line 752, in get_repo_messages
    repo_content = self.get_repo_map()
                   ^^^^^^^^^^^^^^^^^^^
  File "base_coder.py", line 713, in get_repo_map
    cur_msg_text = self.get_cur_message_text()
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "base_coder.py", line 675, in get_cur_message_text
    text += msg["content"] + "\n"
            ~~~~~~~~~~~~~~~^~~~~~
TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'

[PierrunoYT]

Reproduces, and the source is one frame above the traceback. When the model replies with a function call instead of prose, add_assistant_reply_to_cur_messages() appends dict(role="assistant", content=None, function_call=...) — None is the shape the API wants for that message. On the next turn get_cur_message_text() concatenates every msg["content"] to scan the conversation for file and identifier mentions for the repo map, and None + "\n" raises. So it takes a function-calling edit format plus one more user message, with the repo map on.

Three other readers make the same assumption and crash on the same message: get_context_from_history() (the auto-commit message), ChatSummary.summarize_all() (the background summariser), and /copy, which also calls len() on the content. utils.format_messages() already handles both None and multi-part list content correctly — the readers just don't use it.

I hit this in Patch, a fork of aider, and fixed it there (PierrunoYT/patch#124): one helper in utils.py returning a message's text — the string, the joined text parts of a multi-part (image) message, or "" when there is none — used at all four sites. /copy skips past a function-call reply to the last thing the model actually wrote rather than erroring. Tests cover the helper against all four content shapes, plus a regression at each of the four call sites (all four fail without the change).

The change touches aider/utils.py, aider/coders/base_coder.py, aider/history.py and aider/commands.py and applies here unchanged — happy to open a PR.