Function sleeping_retry

Lib/test/support/__init__.py:2724–2755

Wait strategy that applies exponential backoff. Run the loop body until "break" stops the loop. Sleep at each loop iteration, but not at the first iteration. The sleep delay is doubled at each iteration (up to *max_delay* seconds). See busy_retry() documentation for the parame

(timeout, err_msg=None, /,
                     *, init_delay=0.010, max_delay=1.0, error=True)

def sleeping_retry(timeout, err_msg=None, /,
                     *, init_delay=0.010, max_delay=1.0, error=True):
    """
    Wait strategy that applies exponential backoff.

    Run the loop body until "break" stops the loop. Sleep at each loop
    iteration, but not at the first iteration. The sleep delay is doubled at
    each iteration (up to *max_delay* seconds).

    See busy_retry() documentation for the parameters usage.

    Example raising an exception after SHORT_TIMEOUT seconds:

        for _ in support.sleeping_retry(support.SHORT_TIMEOUT):
            if check():
                break

    Example of error=False usage:

        for _ in support.sleeping_retry(support.SHORT_TIMEOUT, error=False):
            if check():
                break
        else:
            raise RuntimeError('my custom error')
    """

    delay = init_delay
    for _ in busy_retry(timeout, err_msg, error=error):
        yield

        time.sleep(delay)
        delay = min(delay * 2, max_delay)


class Stopwatch: