[PATCH 2/8] wsdapi/tests: Add test for duplicate message filtering.

[Huw Davies]

On Mon, Sep 17, 2018 at 09:24:48PM +0100, Owen Rudge wrote:
> On 13/09/2018 11:05, Huw Davies wrote:
> 
> >> +        Sleep(1000);
> >
> > Can't we poll for this?  The tests are starting to take quite a long
> > time to complete, and this doesn't help.
> 
> I'm not sure there is a very good way of avoiding it. We're effectively
> waiting for an extra 2 messages *not* to be received. We can easily test
> when the first message has been received and processed of course, but
> there's no way of identifying when the subsequent messages have been
> received. WSD does not expose any kind of "duplicate message" notification
> that we could listen for.
> 
> What I could do is reduce the delay down from 1000ms to, say, 250ms. The UDP
> messages are sent immediately rather than with a variable delay (as per WSD
> itself), so they should be processed and dispatched quickly. In my tests
> this works OK, but of course it could conceivably be more vulnerable to
> sporadic failures on slow or very busy systems.

How much do we lose by not testing this feature?  If there's no reliable
way to do it then it may be better to simply not.

> I can also try to look at any other delays that are already present in the
> tests and see if they can be reduced/eliminated once this series is
> complete.

That would be good in any case.

Huw.