bec_widgets/tests/conftest.py

import traceback

import pytest
import qtpy.QtCore
from pytestqt.exceptions import TimeoutError as QtBotTimeoutError
from qtpy.QtCore import QTimer


class TestableQTimer(QTimer):
    _instances: list[tuple[QTimer, str, str]] = []
    _current_test_name: str = ""

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        tb = traceback.format_stack()
        init_line = list(filter(lambda msg: "QTimer(" in msg, tb))[-1]
        TestableQTimer._instances.append((self, TestableQTimer._current_test_name, init_line))

    @classmethod
    def check_all_stopped(cls, qtbot):
        def _is_done_or_deleted(t: QTimer):
            try:
                return not t.isActive()
            except RuntimeError as e:
                return "already deleted" in e.args[0]

        def _format_timers(timers: list[tuple[QTimer, str, str]]):
            return "\n".join(
                f"Timer: {t[0]}\n    in test: {t[1]}\n    created at:{t[2]}" for t in timers
            )

        try:
            qtbot.waitUntil(
                lambda: all(_is_done_or_deleted(timer) for timer, _, _ in cls._instances)
            )
        except QtBotTimeoutError as exc:
            active_timers = list(filter(lambda t: t[0].isActive(), cls._instances))
            (t.stop() for t, _, _ in cls._instances)
            raise TimeoutError(
                f"Failed to stop all timers:\n{_format_timers(active_timers)}"
            ) from exc
        cls._instances = []


# To support 'from qtpy.QtCore import QTimer' syntax we just replace this completely for the test session
# see: https://docs.python.org/3/library/unittest.mock.html#where-to-patch
qtpy.QtCore.QTimer = TestableQTimer


@pytest.fixture(autouse=True)
def _capture_test_name_in_qtimer(request):
    TestableQTimer._current_test_name = request.node.name
    yield
    TestableQTimer._current_test_name = ""


@pytest.fixture
def testable_qtimer_class():
    return TestableQTimer