[gevent worker] prevent late monkey-patching in pytest

osprey_worker/conftest.py

@@ -17,6 +17,10 @@
     from _pytest.config.argparsing import Parser
 
 
+# capture launch state before test imports can patch gevent
+_STARTED_PREPATCHED = monkey.is_module_patched('socket')
+
+
 def pytest_addoption(parser: 'Parser') -> None:
     """Register custom pytest options.
 
@@ -69,13 +73,14 @@ def pytest_sessionfinish(session: object, exitstatus: int) -> None:
     the process can stall inside gevent's interpreter finalization and never
     exit, so the integration-tests CI job hangs until its 30-minute timeout.
     Exit immediately here (trylast, so this runs after the junit/terminal
-    hooks) to skip that teardown. Guarded on gevent being active so a plain
-    ``pytest`` run finalizes normally.
+    hooks) to skip that teardown. Guarded on pytest having *started* under the
+    gevent-monkey runner (see ``_STARTED_PREPATCHED``) so a plain ``pytest`` run
+    finalizes normally even if a test module monkey-patched during collection.
     """
     import os
     import sys
 
-    if not monkey.is_module_patched('socket'):
+    if not _STARTED_PREPATCHED:
         return
     sys.stdout.flush()
     sys.stderr.flush()

osprey_worker/src/osprey/worker/lib/discovery/tests/test_discovery.py

@@ -1,6 +1,8 @@
 from gevent import monkey
 
-monkey.patch_all(aggressive=True)  # noqa: E402
+# late monkey-patching corrupts locks during plain pytest collection
+if monkey.is_module_patched('socket'):
+    monkey.patch_all(aggressive=True)
 
 import gevent  # noqa: E402
 import pytest  # noqa: E402

osprey_worker/src/osprey/worker/lib/etcd/tests/conftest.py

@@ -1,8 +1,10 @@
 # flake8: noqa E402
 # ruff: noqa: E402
-from gevent.monkey import patch_all
+from gevent import monkey
 
-patch_all()
+# late monkey-patching corrupts locks during plain pytest collection
+if monkey.is_module_patched('socket'):
+    monkey.patch_all()
 
 import json
 

osprey_worker/src/osprey/worker/lib/instruments/tests/test_concurrency.py

@@ -1,8 +1,9 @@
-# Patch so we can test concurrency
+# late monkey-patching corrupts locks during plain pytest collection
 import gevent
 import gevent.monkey
 
-gevent.monkey.patch_all()
+if gevent.monkey.is_module_patched('socket'):
+    gevent.monkey.patch_all()
 
 from unittest.mock import call  # noqa: E402
 

osprey_worker/tests/test_gevent_collection.py

@@ -0,0 +1,65 @@
+"""Regression tests for plain pytest collection of gevent-patched test modules.
+
+Some test modules under ``osprey_worker`` used to call ``monkey.patch_all`` at
+import time. Under plain ``pytest`` (not the pre-patched integration runner)
+that late patch mutates global gevent state after threading/ssl are already
+imported, raising ``RuntimeError: cannot release un-acquired lock`` during
+collection. The ``pytest_sessionfinish`` force-exit hook then saw socket as
+patched and called ``os._exit``, hiding the terminal traceback and leaving a
+bare exit code 2.
+
+These tests run plain ``pytest --collect-only`` in a child process (so gevent
+is NOT pre-patched) and assert collection succeeds with a normal summary.
+"""
+
+import re
+import subprocess
+import sys
+from pathlib import Path
+
+import pytest
+
+# repo root is three parents up from this file
+_REPO_ROOT = Path(__file__).resolve().parents[2]
+
+# one representative target per import-time gevent patch site:
+# - discovery/tests/test_discovery.py patches in the module body
+# - instruments/tests/test_concurrency.py patches in the module body
+# - etcd/tests/conftest.py patches in the conftest, so collecting any etcd test
+#   exercises it
+_GEVENT_TEST_MODULES = [
+    'osprey_worker/src/osprey/worker/lib/discovery/tests/test_discovery.py',
+    'osprey_worker/src/osprey/worker/lib/instruments/tests/test_concurrency.py',
+    'osprey_worker/src/osprey/worker/lib/etcd/tests/test_dict.py',
+]
+
+
+def _collect_only_plain(target: str) -> subprocess.CompletedProcess[str]:
+    """Run ``pytest --collect-only`` on ``target`` in a plain (non pre-patched) child."""
+    return subprocess.run(
+        [sys.executable, '-m', 'pytest', '--collect-only', '-q', '-p', 'no:cacheprovider', target],
+        cwd=_REPO_ROOT,
+        capture_output=True,
+        text=True,
+        timeout=30,
+    )
+
+
+@pytest.mark.parametrize('target', _GEVENT_TEST_MODULES)
+def test_plain_collection_succeeds(target: str) -> None:
+    module_path = _REPO_ROOT / target
+    assert module_path.exists(), f'{target} does not exist'
+
+    result = _collect_only_plain(target)
+
+    combined = result.stdout + result.stderr
+    assert result.returncode == 0, (
+        f'plain `pytest --collect-only` on {target} exited {result.returncode}\n'
+        f'stdout:\n{result.stdout}\nstderr:\n{result.stderr}'
+    )
+    # the specific late-monkey-patch failure and pytest's collection-error
+    # markers must be absent, and a healthy run reports a nonzero collected
+    # count ("no tests collected in ..." must not match)
+    assert 'cannot release un-acquired lock' not in combined, combined
+    assert 'error during collection' not in combined, combined
+    assert re.search(r'\d+ tests? collected in', result.stdout), result.stdout