Cannot use it in a nested manner

[zachliu]

I'm using it under Python 3.8.4

from time import sleep

from func_timeout import func_set_timeout


@func_set_timeout(1)
def func_1(sec):
    print(f"in func 1, sleeping {sec} sec but will timeout in 1 sec")
    sleep(sec)


@func_set_timeout(1)
def func_2(sec):
    print(f"in func 2, sleeping {sec} sec but will timeout in 1 sec")
    sleep(sec)


@func_set_timeout(5)
def func():
    func_1(2)
    print("in main func")
    func_2(0.3)


if __name__ == "__main__":
    func()

This program would stop at func_1(2) silently
it seems the top level @func_set_timeout(5) swallows all the FunctionTimedOut and doesn't re-raise

[zachliu]

i think this is why but i don't understand the reason behind it

func_timeout/func_timeout/dafunc.py

Lines 69 to 71 in 50baa8d

	except FunctionTimedOut:
	# Don't print traceback to stderr if we time out
	pass

in order to use it in a nested manner, we need to capture the FunctionTimedOut and re-raise as something else such as TimeoutError for it to be captured by the top-level @func_set_timeout(5)

from functools import wraps
from time import sleep
from typing import Any, Callable, Type

from func_timeout import FunctionTimedOut, func_set_timeout


def retry(
    *exceptions: Type[Exception], count: int = 20, wait_time: int = 20,
) -> Callable:
    """Enable retry option for a set of exceptions
    """

    def retry_decorator(func: Callable) -> Callable:
        """Decorator"""

        @wraps(func)
        def func_wrapper(
            *args: Any, **kwargs: Any
        ) -> Any:
            """Function wrapper"""
            for i in range(count):
                try:
                    return func(*args, **kwargs)
                except exceptions as exception:  # pragma: no cover
                    print(
                        f"Retrying {i+1}: exception='{exception}', "
                        f"total {count} retries, wait {wait_time} seconds"
                    )
                    sleep(wait_time)

                    if i == count - 1:
                        if isinstance(exception, FunctionTimedOut):
                            raise TimeoutError("Re-raise as TimeoutError")
                        raise exception

        return func_wrapper

    return retry_decorator


@retry(
    FunctionTimedOut, count=2, wait_time=1,
)
@func_set_timeout(1)
def func_1(sec):
    print(f"in func 1, sleeping {sec} sec but will timeout in 1 sec")
    sleep(sec)


@retry(
    FunctionTimedOut, count=2, wait_time=1,
)
@func_set_timeout(1)
def func_2(sec):
    print(f"in func 2, sleeping {sec} sec but will timeout in 1 sec")
    sleep(sec)


@retry(
    FunctionTimedOut, count=2, wait_time=1,
)
@func_set_timeout(5)
def func():
    func_1(2)
    print("in main func")
    func_2(0.3)


if __name__ == "__main__":
    func()

[kata198]

Sorry for the delay, I've been away.

I've fixed this issue. The change is committed under the currently unreleased 4.4branch (I need to write tests and such)

If you want technical details on why that "pass" statement is there, it's to avoid the default exception handler which we cannot control, and it spams stderr.
You used to be able to override it, but not on anything modern. You can see the spam if you change that "pass" to "raise" and run the test suite.

I've updated the code so that we now explicitly check if we are going to raise the exception into another StoppableThread, in which case 4.4branch now does. Otherwise, (returning to the MainThread or a different type of thread) we continue to eat the error.

The test suite passes with this change, and your testcase also passes. I'll write some test cases to make sure this covers the issue completely, and it stays covered.

Thanks for the report!