Matrix DM room misclassification fixes and detection logic

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

• #51731 fix(matrix): use member_count as DM signal for named DM rooms (#48551)

  merged to main

  files: plugins/platforms/matrix/adapter.py, tests/gateway/test_matrix.py, tests/gateway/test_matrix_project_context_isolation.py

  Show the diff

  • plugins/platforms/matrix/adapter.py

    @@ -3573,21 +3573,29 @@ def _state_event_value(event: Any, key: str) -> Optional[str]:
             return None
     
         async def _get_room_member_count(self, room_id: str) -> Optional[int]:
    +        # Tier 1: state_store (fast, cache-backed).
             state_store = (
                 getattr(self._client, "state_store", None) if self._client else None
             )
    -        if not state_store:
    -            return None
    -        try:
    -            members = await state_store.get_members(room_id)
    -        except Exception:
    -            return None
    -        if members is None:
    -            return None
    -        try:
    -            return len(members)
    -        except TypeError:
    -            return None
    +        if state_store:
    +            try:
    +                members = await state_store.get_members(room_id)
    +                if members is not None:
    +                    return len(members)
    +            except Exception:
    +                pass
    +
    +        # Tier 2: API fallback (direct server query) when the cache is empty.
    +        client = getattr(self, "_client", None)
    +        if client is not None and hasattr(client, "joined_members"):
    +            try:
    +                resp = await client.joined_members(room_id)
    +                if getattr(resp, "members", None) is not None:
    +                    return len(resp.members)
    +            except Exception:
    +                pass
    +
    +        return None
     
         async def _get_room_name(self, room_id: str) -> Optional[str]:
             if not self._client or not hasattr(self._client, "get_state_event"):
    @@ -3674,8 +3682,23 @@ async def _resolve_room_identity(
             member_count = await self._get_room_member_count(room_id)
             has_explicit_name = bool(room_name)
             is_direct = bool(self._dm_rooms.get(room_id, False))
    -        conflict = bool(is_direct and has_explicit_name)
    -        chat_type = "dm" if is_direct and not has_explicit_name else "room"
    +        # member_count is the primary DM signal: <=2 members means this is
    +        # necessarily a 1:1 conversation (or self-DM), regardless of m.direct
    +        # or room name. Most Matrix clients auto-name DM rooms (e.g.
    +        # "Alice & Bot"), so the old `not has_explicit_name` check
    +        # misclassified virtually all client-created DMs as rooms. Falls back
    +        # to the m.direct + name heuristic when the count is unavailable (e.g.
    +        # state_store and API query both fail). A room that grew to 3+ members
    +        # but is still in stale m.direct is correctly classified as a room.
    +        is_likely_dm = (member_count is not None and member_count <= 2) or (
    +            is_direct and not has_explicit_name
    +        )
    +        conflict = bool(
    +            is_direct
    +            and has_explicit_name
    +            and (member_count is None or member_count > 2)
    +        )
    +        chat_type = "dm" if is_likely_dm else "room"
             display_name = room_name or canonical_alias or room_id
     
             identity = MatrixRoomIdentity(

  • tests/gateway/test_matrix.py

    @@ -502,8 +502,9 @@ async def test_m_direct_room_is_dm(self):
             assert await self.adapter._is_dm_room("!dm_room:ex.org") is True
     
         @pytest.mark.asyncio
    -    async def test_named_two_member_room_is_not_dm(self):
    -        """A named two-member room must remain a room, not a DM."""
    +    async def test_named_two_member_room_is_dm_by_member_count(self):
    +        """A named two-member room NOT in m.direct is treated as a DM because
    +        <=2 members means it's necessarily a 1:1 conversation."""
             self.adapter._joined_rooms = {"!project:ex.org"}
             self.adapter._dm_rooms = {}
             self.adapter._client = MagicMock()
    @@ -519,14 +520,41 @@ async def test_named_two_member_room_is_not_dm(self):
     
             identity = await self.adapter._resolve_room_identity("!project:ex.org")
     
    -        assert identity.chat_type == "room"
    +        assert identity.chat_type == "dm"
             assert identity.display_name == "Project Room"
             assert identity.joined_member_count == 2
    -        assert await self.adapter._is_dm_room("!project:ex.org") is False
    +        assert await self.adapter._is_dm_room("!project:ex.org") is True
    +
    +    @pytest.mark.asyncio
    +    async def test_named_two_member_dm_is_dm(self):
    +        """A named two-member room in m.direct is a DM (not a room).
    +
    +        Most Matrix clients auto-name DM rooms (e.g. "Alice & Bot"), so the
    +        old `not has_explicit_name` override misclassified them as rooms.
    +        """
    +        self.adapter._joined_rooms = {"!named_dm:ex.org"}
    +        self.adapter._dm_rooms = {"!named_dm:ex.org": True}
    +        self.adapter._client = MagicMock()
    +        self.adapter._client.get_state_event = AsyncMock(
    +            side_effect=lambda room_id, event_type: {"name": "Alice & Bot"}
    +            if event_type == "m.room.name"
    +            else (_ for _ in ()).throw(Exception("no alias"))
    +        )
    +        self.adapter._client.state_store = MagicMock()
    +        self.adapter._client.state_store.get_members = AsyncMock(
    +            return_value=["@bot:ex.org", "@alice:ex.org"]
    +        )
    +
    +        identity = await self.adapter._resolve_room_identity("!named_dm:ex.org")
    +
    +        assert identity.chat_type == "dm"
    +        assert identity.conflict is False
    +        assert identity.joined_member_count == 2
    +        assert await self.adapter._is_dm_room("!named_dm:ex.org") is True
     
         @pytest.mark.asyncio
         async def test_named_room_overrides_stale_dm_cache(self):
    -        """Explicit room names should defeat stale/conflicting m.direct data."""
    +        """Explicit room names defeat stale/conflicting m.direct data when 3+ members."""
             self.adapter._joined_rooms = {"!stale:ex.org"}
             self.adapter._dm_rooms = {"!stale:ex.org": True}
             self.adapter._client = MagicMock()
    @@ -536,12 +564,15 @@ async def test_named_room_overrides_stale_dm_cache(self):
                 else (_ for _ in ()).throw(Exception("no alias"))
             )
             self.adapter._client.state_store = MagicMock()
    -        self.adapter._client.state_store.get_members = AsyncMock(return_value=["@bot:ex.org", "@alice:ex.org"])
    +        self.adapter._client.state_store.get_members = AsyncMock(
    +            return_value=["@bot:ex.org", "@alice:ex.org", "@bob:ex.org"]
    +        )
     
             identity = await self.adapter._resolve_room_identity("!stale:ex.org")
     
             assert identity.chat_type == "room"
             assert identity.conflict is True
    +        assert identity.joined_member_count == 3
             assert await self.adapter._is_dm_room("!stale:ex.org") is False
     
         @pytest.mark.asyncio
    @@ -2057,7 +2088,7 @@ def handle_sync(sync_data):
             fake_client.join_room.assert_awaited_once()
             assert "!room:example.org" in adapter._joined_rooms
             assert len(captured) == 1
    -        assert captured[0].source.chat_type == "group"
    +        assert captured[0].source.chat_type == "dm"
     
         @pytest.mark.asyncio
         async def test_seconds_timestamp_is_not_treated_as_milliseconds(self):

  • tests/gateway/test_matrix_project_context_isolation.py

    @@ -168,6 +168,9 @@ async def test_matrix_project_context_survives_sequential_messages():
     @pytest.mark.asyncio
     async def test_matrix_session_scope_auto_and_thread_preserve_synthetic_threads():
         adapter = _make_adapter()
    +    # Override member_count to 3 so the named project room is NOT classified as
    +    # a DM (the DM fix uses member_count <= 2 as the primary DM signal).
    +    adapter._get_room_member_count = AsyncMock(return_value=3)
         adapter._auto_thread = True
         adapter._matrix_session_scope = "auto"
         auto_source = await _source_for(adapter, PROJECT_B_ROOM_ID, "$auto")