Re: treatment of U+002E that is produced by NFKC

[Erik van der Poel]

> Interesting.  As far as I can tell from RFC 3490, I think the libidn
> behaviour is what follows from the specification.  The specification
> doesn't say anything about treating U+2024 as a label separator that I
> could find.  Do you agree with this?

Yes, I agree.

> If so, I think the first step is
> to update the RFC, and when that is done we can adapt the new behaviour
> in libidn.

Sure, that is one way to deal with this. Libidn users may not be
clamoring for a resolution. Other implementations may be in more of a
rush to resolve the conflict. (I work for Google.)

> If libidn implements RFC 3490 incorrectly, we should definitely fix
> that.  Right now I don't understand what part of RFC 3490 we implement
> incorrectly.  So please explain further how the RFC 3490 language and
> libidn differ.
>
> I think one could argue more convincingly that MSIE/Firefox implements
> RFC 3490 incorrectly here.  U+2024 isn't a label separator according to
> RFC 3490, but they treat it as if it were.

Yes, one could certainly argue that MSIE and Firefox implement RFC
3490 incorrectly, particularly if you read section 4 steps 4) and 5)
carefully. However, I also believe that MSIE and Firefox chose a
reasonable behavior and that it seems somewhat unlikely that they will
change their behavior, given that the IDNA200X discussions already
appear to be moving in their direction.

Erik