import asyncio import time import sys import pytest from textual.app import App pytestmark = pytest.mark.skipif( sys.platform != "win32", reason="We only need to test this on Windows." ) def test_win_sleep_timer_is_cancellable(): """Regression test for https://github.com/Textualize/textual/issues/2711. When we exit an app with a "long" timer, everything asyncio-related should shutdown quickly. So, we create an app with a timer that triggers every SLEEP_FOR seconds and we shut the app down immediately after creating it. `asyncio` should be done quickly (i.e., the timer was cancelled) and thus the total time this takes should be considerably lesser than the time we originally set the timer for. """ SLEEP_FOR = 10 class WindowsIntervalBugApp(App[None]): def on_mount(self) -> None: self.set_interval(SLEEP_FOR, lambda: None) def key_e(self): self.exit() async def actual_test(): async with WindowsIntervalBugApp().run_test() as pilot: await pilot.press("e") start = time.perf_counter() asyncio.run(actual_test()) end = time.perf_counter() assert end - start < 1