frame_manager.py 文件源码

def __init__(self, frame: Frame, _type: str, expr: str, timeout: float,
                 *args: Any, interval: float = 0) -> None:
        """Make new wait task.

        :arg float timeout: msec to wait for task [default 30_000 [msec]].
        :arg float interval: msec to poll for task [default timeout / 1000].
        """
        if _type not in ['function', 'selector']:
            raise ValueError('Unsupported type for WaitTask: ' + _type)
        super().__init__()
        self.__frame: Frame = frame
        self.__type = _type
        self.expr = expr
        self.__timeout = timeout / 1000  # sec
        self.__interval = interval / 1000 or self.__timeout / 100  # sec
        self.__runCount: int = 0
        self.__terminated = False
        self.__done = False
        frame._waitTasks.add(self)
        # Since page navigation requires us to re-install the pageScript,
        # we should track timeout on our end.
        self.__loop = asyncio.get_event_loop()
        self.__timeoutTimer = self.__loop.call_later(
            self.__timeout,
            lambda: self.terminate(
                BrowserError(f'waiting failed: timeout {timeout}ms exceeded')
            )
        )
        asyncio.ensure_future(self.rerun(True))