Import AITURK IDE 1.0.0-beta.1 from Hermes 63279301; preserve MIT license

tests/tools/test_mcp_transport_group_reconnect.py

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+"""Regression tests for issue #66092.
+
+Streamable-HTTP / SSE MCP transports run their stream pump inside an anyio
+TaskGroup. A transient stream drop (idle timeout, brief backend blip) surfaces
+as a ``BaseExceptionGroup`` escaping the transport context manager. Before the
+fix that group reached ``run()``'s error path, which applied exponential
+backoff and eventually parked the server for 300s and deregistered its tools —
+a multi-minute tool outage for a sub-second glitch.
+
+``_run_http`` now converts such a transport TaskGroup failure into a clean
+``"reconnect"`` (immediate rebuild, no backoff/park), while still propagating
+real shutdown/cancellation and genuine connect/handshake failures.
+"""
+
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+from tools.mcp_tool import MCPServerTask
+
+
+def _group(*excs) -> BaseExceptionGroup:
+    return BaseExceptionGroup("transport drop", list(excs))
+
+
+# ── Unit coverage for the decision helper ────────────────────────────────────
+
+class TestReconnectOrReraiseGroup:
+    def test_live_session_transient_drop_reconnects(self):
+        task = MCPServerTask("t")
+        task._ready.set()  # a live session was established this attempt
+        assert task._reconnect_or_reraise_group(
+            _group(ConnectionError("sse stream dropped"))
+        ) == "reconnect"
+
+
+    def test_no_live_session_reraises_for_backoff(self):
+        task = MCPServerTask("t")
+        # _ready NOT set: a connect/handshake failure, not a transient drop —
+        # let run()'s backoff handle it instead of hot-looping.
+        with pytest.raises(BaseExceptionGroup):
+            task._reconnect_or_reraise_group(_group(ConnectionError("handshake")))
+
+
+# ── Integration coverage: real _run_http new-HTTP branch ─────────────────────
+
+class _RaisingTransportCM:
+    """Fake streamable-HTTP transport whose __aexit__ raises a group, mimicking
+    the SDK's anyio TaskGroup tearing down on a stream drop."""
+
+    def __init__(self, exc):
+        self._exc = exc
+
+    async def __aenter__(self):
+        return (object(), object(), lambda: "session-id")
+
+    async def __aexit__(self, *exc_info):
+        raise self._exc
+
+
+class _FakeSession:
+    async def initialize(self):
+        return object()
+
+
+class _FakeSessionCM:
+    async def __aenter__(self):
+        return _FakeSession()
+
+    async def __aexit__(self, *exc_info):
+        return False
+
+
+def _make_http_task(monkeypatch, transport_exc):
+    task = MCPServerTask("http-drop")
+
+    monkeypatch.setattr("tools.mcp_tool._MCP_HTTP_AVAILABLE", True, raising=False)
+    monkeypatch.setattr("tools.mcp_tool._MCP_NEW_HTTP", True, raising=False)
+    monkeypatch.setattr(
+        "tools.mcp_tool.streamable_http_client",
+        lambda url, http_client=None: _RaisingTransportCM(transport_exc),
+        raising=False,
+    )
+    monkeypatch.setattr(
+        "tools.mcp_tool.ClientSession",
+        lambda *a, **k: _FakeSessionCM(),
+        raising=False,
+    )
+
+    async def _no_discover(self):
+        return None
+
+    async def _reconnect_lifecycle(self):
+        return "reconnect"
+
+    monkeypatch.setattr(MCPServerTask, "_discover_tools", _no_discover)
+    monkeypatch.setattr(MCPServerTask, "_wait_for_lifecycle_event", _reconnect_lifecycle)
+    return task
+
+
+def test_run_http_transport_group_returns_reconnect(monkeypatch):
+    task = _make_http_task(monkeypatch, _group(ConnectionError("stream dropped")))
+    reason = asyncio.run(task._run_http({"url": "http://127.0.0.1:9/mcp"}))
+    assert reason == "reconnect"
+    # We had a live session; readiness stays set for run() to clear on re-entry.
+    assert task._ready.is_set()
+
+
+def test_run_http_transport_group_reraises_on_shutdown(monkeypatch):
+    task = _make_http_task(monkeypatch, _group(ConnectionError("stream dropped")))
+    task._shutdown_event.set()
+    with pytest.raises(BaseExceptionGroup):
+        asyncio.run(task._run_http({"url": "http://127.0.0.1:9/mcp"}))