ioloop_test.py 文件源码

def test_exception_logging(self):
        """Uncaught exceptions get logged by the IOLoop."""
        # Use a NullContext to keep the exception from being caught by
        # AsyncTestCase.
        with NullContext():
            self.io_loop.add_callback(lambda: 1 / 0)
            self.io_loop.add_callback(self.stop)
            with ExpectLog(app_log, "Exception in callback"):
                self.wait()