[Python-ideas] PEP 3156/Tulip: Extensible EventLoop interface

[Guido van Rossum]

On Wed, Feb 6, 2013 at 4:11 PM, Guido van Rossum <guido at python.org> wrote:
> On Wed, Feb 6, 2013 at 3:58 PM, Richard Oudkerk <shibturn at gmail.com> wrote:
>> On 06/02/2013 10:43pm, Guido van Rossum wrote:
>>>
>>> Me neither.:-(
>>>
>>> The message "Exception in task" means that it is a task that raises an
>>> exception. I used to ignore these; now I log them always, but ideally
>>> they should only be logged when whoever waits for the Task doesn't
>>> catch them (or, better, when nobody waits for the task). I tried to
>>> implement that part but I couldn't get it to work (yet) -- I will have
>>> to get back to this at some point, because accurate exception logging
>>> (never silent, but not too spammy either) is very important for a good
>>> user experience.
>>>
>>> But it remains a mystery why they sometimes show and not other times.
>>> It suggests there's some indeterminate timing in some tests. If it
>>> happens only the first time when the tests are run this usually points
>>> to a timing behavior that's different when the source code is parsed
>>> as opposed to read from a .pyc file.
>>
>>
>> Commenting out the one use of suppress_log_errors() makes the "expected
>> errors" appear on Linux too.  But I would have thought that that would only
>> effect the test which uses suppress_log_errors().
>>
>> diff -r 65c456e2c20e tulip/events_test.py
>> --- a/tulip/events_test.py      Wed Feb 06 19:08:14 2013 +0000
>> +++ b/tulip/events_test.py      Wed Feb 06 23:51:32 2013 +0000
>> @@ -508,7 +508,7 @@
>>          self.assertFalse(sock.close.called)
>>
>>      def test_accept_connection_exception(self):
>> -        self.suppress_log_errors()
>> +        #self.suppress_log_errors()
>>
>>          sock = unittest.mock.Mock()
>>          sock.accept.side_effect = socket.error
>
> Good catch! What's going on is that the super().tearDown() call was
> missing from EventLoopTestsMixin. I'll fix that -- then we'll have to
> separately add suppress_log_errors() calls to various tests (I'll do
> that at a slower pace).

Should all be fixed now. (Please check on Windows, I can't check it right now.)

-- 
--Guido van Rossum (python.org/~guido)