Hermes-agent

tests/agent/lsp/test_lifecycle.py

@@ -0,0 +1,144 @@
+"""Tests for service-singleton lifecycle: atexit handler, idempotent shutdown.
+
+These cover the exit-cleanup behavior added to plug the language-server
+process leak — without the atexit hook, ``hermes chat`` exits while
+pyright/gopls/etc. are still alive on the host.
+"""
+from __future__ import annotations
+
+import atexit
+from unittest.mock import MagicMock
+
+import pytest
+
+from agent import lsp as lsp_module
+
+
+@pytest.fixture(autouse=True)
+def _reset_singleton():
+    """Force a clean module state before each test.
+
+    Tests in this file share process-global state (the lazy
+    singleton + atexit registration flag); reset both before and
+    after every test so order doesn't matter.
+    """
+    lsp_module._service = None
+    lsp_module._atexit_registered = False
+    yield
+    lsp_module._service = None
+    lsp_module._atexit_registered = False
+
+
+def test_get_service_registers_atexit_handler_once(monkeypatch):
+    """First call to ``get_service`` must register an atexit handler;
+    subsequent calls must NOT register another one (Python's ``atexit``
+    runs every registered callable, so a duplicate would shutdown
+    twice — harmless but wasteful)."""
+    fake_svc = MagicMock()
+    fake_svc.is_active.return_value = True
+    monkeypatch.setattr(
+        lsp_module.LSPService, "create_from_config", classmethod(lambda cls: fake_svc)
+    )
+
+    registrations = []
+
+    def fake_register(fn):
+        registrations.append(fn)
+
+    monkeypatch.setattr(atexit, "register", fake_register)
+
+    a = lsp_module.get_service()
+    b = lsp_module.get_service()
+    c = lsp_module.get_service()
+
+    assert a is fake_svc
+    assert b is fake_svc
+    assert c is fake_svc
+    assert len(registrations) == 1
+    # The registered callable must be our internal shutdown wrapper.
+    assert registrations[0] is lsp_module._atexit_shutdown
+
+
+def test_atexit_shutdown_calls_shutdown_service(monkeypatch):
+    """The atexit-registered wrapper invokes ``shutdown_service`` and
+    swallows any exception — by the time atexit fires, the user has
+    already seen the response and a noisy traceback would be clutter."""
+    called = []
+    monkeypatch.setattr(
+        lsp_module, "shutdown_service", lambda: called.append("shutdown")
+    )
+    lsp_module._atexit_shutdown()
+    assert called == ["shutdown"]
+
+
+def test_atexit_shutdown_swallows_exceptions(monkeypatch):
+    def boom():
+        raise RuntimeError("server already dead")
+
+    monkeypatch.setattr(lsp_module, "shutdown_service", boom)
+    # Must not raise.
+    lsp_module._atexit_shutdown()
+
+
+def test_shutdown_service_idempotent(monkeypatch):
+    """Calling shutdown twice must be safe — first call cleans up,
+    second call no-ops (nothing to shut down)."""
+    fake_svc = MagicMock()
+    fake_svc.is_active.return_value = True
+    fake_svc.shutdown = MagicMock()
+    monkeypatch.setattr(
+        lsp_module.LSPService, "create_from_config", classmethod(lambda cls: fake_svc)
+    )
+    monkeypatch.setattr(atexit, "register", lambda fn: None)
+
+    lsp_module.get_service()
+    lsp_module.shutdown_service()
+    lsp_module.shutdown_service()  # must not raise
+
+    assert fake_svc.shutdown.call_count == 1
+
+
+def test_shutdown_service_no_op_when_never_started():
+    """Calling shutdown without ever creating the service is safe."""
+    lsp_module.shutdown_service()  # must not raise
+
+
+def test_shutdown_service_swallows_exception(monkeypatch):
+    """An exception during ``svc.shutdown()`` must not propagate —
+    the caller (often atexit) has nothing useful to do with it."""
+    fake_svc = MagicMock()
+    fake_svc.is_active.return_value = True
+    fake_svc.shutdown = MagicMock(side_effect=RuntimeError("kill -9 already"))
+    monkeypatch.setattr(
+        lsp_module.LSPService, "create_from_config", classmethod(lambda cls: fake_svc)
+    )
+    monkeypatch.setattr(atexit, "register", lambda fn: None)
+
+    lsp_module.get_service()
+    lsp_module.shutdown_service()  # must not raise
+
+
+def test_get_service_returns_none_for_inactive_service(monkeypatch):
+    """A service whose ``is_active()`` returns False is treated as
+    not running — callers see ``None`` and fall back."""
+    fake_svc = MagicMock()
+    fake_svc.is_active.return_value = False
+    monkeypatch.setattr(
+        lsp_module.LSPService, "create_from_config", classmethod(lambda cls: fake_svc)
+    )
+    monkeypatch.setattr(atexit, "register", lambda fn: None)
+
+    assert lsp_module.get_service() is None
+    # Subsequent call returns None too — but the inactive instance is
+    # cached so we don't re-build it on every check.
+    assert lsp_module.get_service() is None
+
+
+def test_get_service_returns_none_when_create_fails(monkeypatch):
+    """Service factory returning ``None`` (no config, etc.) propagates."""
+    monkeypatch.setattr(
+        lsp_module.LSPService, "create_from_config", classmethod(lambda cls: None)
+    )
+    monkeypatch.setattr(atexit, "register", lambda fn: None)
+
+    assert lsp_module.get_service() is None