Add test for default Expect handler

[redixin]

Server should return 417 if any of the expectations cannot be met.

http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.20

[redixin]

Currently expect handler called only if value of Expect header is "100-continue"

It would be much better if default handler could return 417 in case of unknown value of this field.

[asvetlov]

Sorry for delay.

I think the current behavior should be fixed.

Please provide a patch.

@fafhrd91 you've added support for Expect header.
Do you have an objection for shrinking allowed cases?

[fafhrd91]

+1

[redixin]

I have a doubt. In fact 100-continue is only one known Expect header. This change makes code more strict but slightly harder to use.

[redixin]

@asvetlov ping

[asvetlov]

Let's postpone it until aiohttp 0.19 release

[lock]

This thread has been automatically locked since there has not been
any recent activity after it was closed. Please open a new issue for
related bugs.

If you feel like there's important points made in this discussion,
please include those exceprts into that new issue.