fix(gateway): isolate telegram forum topic sessions

tests/gateway/test_base_topic_sessions.py

@@ -0,0 +1,135 @@
+"""Tests for BasePlatformAdapter topic-aware session handling."""
+
+import asyncio
+from types import SimpleNamespace
+
+import pytest
+
+from gateway.config import Platform, PlatformConfig
+from gateway.platforms.base import BasePlatformAdapter, MessageEvent, SendResult
+from gateway.session import SessionSource, build_session_key
+
+
+class DummyTelegramAdapter(BasePlatformAdapter):
+    def __init__(self):
+        super().__init__(PlatformConfig(enabled=True, token="fake-token"), Platform.TELEGRAM)
+        self.sent = []
+        self.typing = []
+
+    async def connect(self) -> bool:
+        return True
+
+    async def disconnect(self) -> None:
+        return None
+
+    async def send(self, chat_id, content, reply_to=None, metadata=None) -> SendResult:
+        self.sent.append(
+            {
+                "chat_id": chat_id,
+                "content": content,
+                "reply_to": reply_to,
+                "metadata": metadata,
+            }
+        )
+        return SendResult(success=True, message_id="1")
+
+    async def send_typing(self, chat_id: str, metadata=None) -> None:
+        self.typing.append({"chat_id": chat_id, "metadata": metadata})
+        return None
+
+    async def get_chat_info(self, chat_id: str):
+        return {"id": chat_id}
+
+
+def _make_event(chat_id: str, thread_id: str, message_id: str = "1") -> MessageEvent:
+    return MessageEvent(
+        text="hello",
+        source=SessionSource(
+            platform=Platform.TELEGRAM,
+            chat_id=chat_id,
+            chat_type="group",
+            thread_id=thread_id,
+        ),
+        message_id=message_id,
+    )
+
+
+class TestBasePlatformTopicSessions:
+    @pytest.mark.asyncio
+    async def test_handle_message_does_not_interrupt_different_topic(self, monkeypatch):
+        adapter = DummyTelegramAdapter()
+        adapter.set_message_handler(lambda event: asyncio.sleep(0, result=None))
+
+        active_event = _make_event("-1001", "10")
+        adapter._active_sessions[build_session_key(active_event.source)] = asyncio.Event()
+
+        scheduled = []
+
+        def fake_create_task(coro):
+            scheduled.append(coro)
+            coro.close()
+            return SimpleNamespace()
+
+        monkeypatch.setattr(asyncio, "create_task", fake_create_task)
+
+        await adapter.handle_message(_make_event("-1001", "11"))
+
+        assert len(scheduled) == 1
+        assert adapter._pending_messages == {}
+
+    @pytest.mark.asyncio
+    async def test_handle_message_interrupts_same_topic(self, monkeypatch):
+        adapter = DummyTelegramAdapter()
+        adapter.set_message_handler(lambda event: asyncio.sleep(0, result=None))
+
+        active_event = _make_event("-1001", "10")
+        adapter._active_sessions[build_session_key(active_event.source)] = asyncio.Event()
+
+        scheduled = []
+
+        def fake_create_task(coro):
+            scheduled.append(coro)
+            coro.close()
+            return SimpleNamespace()
+
+        monkeypatch.setattr(asyncio, "create_task", fake_create_task)
+
+        pending_event = _make_event("-1001", "10", message_id="2")
+        await adapter.handle_message(pending_event)
+
+        assert scheduled == []
+        assert adapter.get_pending_message(build_session_key(pending_event.source)) == pending_event
+
+    @pytest.mark.asyncio
+    async def test_process_message_background_replies_in_same_topic(self):
+        adapter = DummyTelegramAdapter()
+        typing_calls = []
+
+        async def handler(_event):
+            await asyncio.sleep(0)
+            return "ack"
+
+        async def hold_typing(_chat_id, interval=2.0, metadata=None):
+            typing_calls.append({"chat_id": _chat_id, "metadata": metadata})
+            await asyncio.Event().wait()
+
+        adapter.set_message_handler(handler)
+        adapter._keep_typing = hold_typing
+
+        event = _make_event("-1001", "17585")
+        await adapter._process_message_background(event, build_session_key(event.source))
+
+        assert adapter.sent == [
+            {
+                "chat_id": "-1001",
+                "content": "ack",
+                "reply_to": "1",
+                "metadata": {"thread_id": "17585"},
+            }
+        ]
+        assert typing_calls == [
+            {
+                "chat_id": "-1001",
+                "metadata": {"thread_id": "17585"},
+            }
+        ]