Files
seedPass/src/tests/test_file_lock.py
2025-06-29 20:56:06 -04:00

44 lines
1.2 KiB
Python

import multiprocessing as mp
import time
from pathlib import Path
import pytest
from utils.file_lock import exclusive_lock
def _hold_lock(path: Path, hold_time: float, started: mp.Event):
with exclusive_lock(path):
started.set()
time.sleep(hold_time)
def _try_lock(path: Path, wait_time: mp.Value):
t0 = time.perf_counter()
with exclusive_lock(path):
wait_time.value = time.perf_counter() - t0
def test_exclusive_lock_blocks_until_released(tmp_path: Path):
file_path = tmp_path / "locktest.txt"
started = mp.Event()
wait_time = mp.Value("d", 0.0)
p1 = mp.Process(target=_hold_lock, args=(file_path, 1.0, started))
p2 = mp.Process(target=_try_lock, args=(file_path, wait_time))
p1.start()
started.wait()
time.sleep(0.1)
p2.start()
p1.join()
p2.join()
# CI runners can be jittery; allow generous slack around the 1s lock hold time
# Different operating systems spawn processes at slightly different speeds
# which can shift the measured wait time by a few hundred milliseconds. A
# wider tolerance keeps the test stable across platforms.
assert wait_time.value == pytest.approx(1.0, abs=0.5)