ResourceWarning in downloader

[dstansby]

I'm seeing the following warning in the pfsspy tests. Not entirely sure what's causing it, but thought I would leave this here so there's a paper trail if anyone wants to investigate further:

 _______________________ ERROR at setup of test_adapt_map _______________________

cls = <class '_pytest.runner.CallInfo'>
func = <function call_runtest_hook.<locals>.<lambda> at 0x7f500bc548b0>
when = 'setup'
reraise = (<class '_pytest.outcomes.Exit'>, <class 'KeyboardInterrupt'>)

    @classmethod
    def from_call(
        cls,
        func: "Callable[[], TResult]",
        when: "Literal['collect', 'setup', 'call', 'teardown']",
        reraise: Optional[
            Union[Type[BaseException], Tuple[Type[BaseException], ...]]
        ] = None,
    ) -> "CallInfo[TResult]":
        excinfo = None
        start = timing.time()
        precise_start = timing.perf_counter()
        try:
>           result: Optional[TResult] = func()

/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/_pytest/runner.py:311: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/_pytest/runner.py:255: in <lambda>
    lambda: ihook(item=item, **kwds), when=when, reraise=reraise
/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/pluggy/hooks.py:286: in __call__
    return self._hookexec(self, self.get_hookimpls(), kwargs)
/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/pluggy/manager.py:93: in _hookexec
    return self._inner_hookexec(hook, methods, kwargs)
/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/pluggy/manager.py:84: in <lambda>
    self._inner_hookexec = lambda hook, methods, kwargs: hook.multicall(
/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/_pytest/unraisableexception.py:83: in pytest_runtest_setup
    yield from unraisable_exception_runtest_hook()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

    def unraisable_exception_runtest_hook() -> Generator[None, None, None]:
        with catch_unraisable_exception() as cm:
            yield
            if cm.unraisable:
                if cm.unraisable.err_msg is not None:
                    err_msg = cm.unraisable.err_msg
                else:
                    err_msg = "Exception ignored in"
                msg = f"{err_msg}: {cm.unraisable.object!r}\n\n"
                msg += "".join(
                    traceback.format_exception(
                        cm.unraisable.exc_type,
                        cm.unraisable.exc_value,
                        cm.unraisable.exc_traceback,
                    )
                )
>               warnings.warn(pytest.PytestUnraisableExceptionWarning(msg))
E               pytest.PytestUnraisableExceptionWarning: Exception ignored in: <socket.socket fd=-1, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=6>
E               
E               Traceback (most recent call last):
E                 File "/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/parfive/downloader.py", line 527, in _http_download_worker
E                   await queue.put((offset, chunk))
E               ResourceWarning: unclosed <socket.socket fd=24, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=6, laddr=('10.1.0.4', 55242), raddr=('146.5.21.61', 443)>

/opt/hostedtoolcache/Python/3.8.6/x64/lib/python3.8/site-packages/_pytest/unraisableexception.py:78: PytestUnraisableExceptionWarning

[Cadair]

spotted a few of these in the sunpy tests as well, not got a clue where to start.

[Cadair]

@dstansby have you seen any of these recently?