qtbot.waitCallback

[The-Compiler]

I think we talked about this but never really opened an issue.

I generalized by code in qutebrowser a bit today:

class CallbackChecker(QObject):

    """Check if a value provided by a callback is the expected one."""

    got_result = pyqtSignal(object)
    UNSET = object()

    def __init__(self, qtbot, parent=None):
        super().__init__(parent)
        self._qtbot = qtbot
        self._result = self.UNSET

    def callback(self, result):
        self._result = result
        self.got_result.emit(result)

    def check(self, expected):
        if self._result is self.UNSET:
            with self._qtbot.waitSignal(self.got_result):
                pass
        assert self._result == expected


@pytest.fixture
def callback_checker(qtbot):
    return CallbackChecker(qtbot)

Example usage:

def test_foo(callback_checker, webengineview)
    expected = 2
    webengineview.page().runJavaScript('1 + 1', callback_checker.callback)
    callback_checker.check(expected)

Next step would be to add this to pytest-qt, which I'll hopefully do soon™

[nicoddemus]

OK, thanks! 😁

What are you planning, something like:

with qtbot.waitCallback(timeout=200, raising=False) as callback:
    webengineview.page().runJavaScript('1 + 1', callback)
assert callback.args == (2,)

?

(If I understood correctly, never used callbacks from Qt like this)

@fogo might want to chip in, he's being using the javascript engine lately.

[The-Compiler]

Sounds good to me, though I'd probably make .args a list like SignalBlocker.args