[Python lark-oapi 1.6.7] InboundMessage.mentioned_bot is always False for IM messages

Environment

• Package: lark-oapi 1.6.7 (Python)
• Python: 3.9+
• Affected path: lark_oapi/channel/normalize/pipeline.py

Summary

InboundMessage.mentioned_bot is unconditionally False for all IM (text/post) messages, even when the bot is explicitly mentioned and the bot identity is fully resolved.

Root Cause

Two compounding omissions in lark_oapi/channel/normalize/pipeline.py:

1. bot_open_id not passed to extract_mentions (line 163)

# pipeline.py:163 — current (broken)
ext = extract_mentions(raw_mentions)

mentions.py:147 only sets ext.mentioned_bot = True when bot_open_id and parsed.open_id == bot_open_id. Since bot_open_id is never passed, ext.mentioned_bot stays False for every IM message.

2. mentioned_bot not forwarded to InboundMessage (lines 253-266)

Even if ext.mentioned_bot were computed, it is never passed to the InboundMessage(...) constructor — only mentions= and mentioned_all= are. The field falls back to its default False (types.py:387). pipeline.py contains no reference to mentioned_bot at all.

Evidence: SDK works around its own bug internally

policy_gate.py:142-143 re-computes the bot-mention check inline rather than trusting msg.mentioned_bot:

mentioned_bot = bool(
    bot_open_id and any(m.open_id == bot_open_id for m in msg.mentions)
)

This confirms the maintainers know the field is unreliable; the internal gate self-heals, but the public-facing field exposed to on("message") consumers was never fixed.

Contrast with the comment path (correct)

comment.py:112 computes mentioned_bot_flag and :137 passes mentioned_bot=mentioned_bot_flag to the comment event. Only the IM path is broken.

Impact

Any consumer reading msg.mentioned_bot in an on("message") handler always receives False, causing "bot is @-mentioned in a group but does not respond" bugs. Verified empirically: with the bot present in mentions and bot_identity resolved, msg.mentioned_bot was still False.

Suggested Fix

In pipeline.py, obtain bot_open_id (same source as policy_gate), pass it to extract_mentions, and forward the result:

bot_open_id = getattr(self._cfg.app, "bot_open_id", None)
ext = extract_mentions(raw_mentions, bot_open_id=bot_open_id)
...
return InboundMessage(
    ...
    mentions=mentions,
    mentioned_all=mentioned_all,
    mentioned_bot=ext.mentioned_bot,   # ADD THIS
    ...
)

Start in lark_oapi/channel/normalize/pipeline.py and compare its IM-message flow with mentions.py, policy_gate.py, and comment.py. Trace bot_open_id and the InboundMessage constructor; done means an explicitly mentioned bot produces mentioned_bot=True for IM messages while existing mention fields remain intact.