[Email-SIG] Double boundaries

[Barry Warsaw]

On Wed, 2004-05-12 at 09:49, Anthony Baxter wrote:
> Barry Warsaw wrote:
> > One of Anthony's torture tests includes a double boundary, e.g.
> > 
> > ...
> > Content-type: multipart/x-foo; boundary=BBB
> > 
> > ...
> > --BBB
> > --BBB
> > 
> > ...
> > 
> > --BBB--
> > 
> > Now, his expected output would ignore the second of the double
> > boundaries.  The current FeedParser injects basically an empty
> > text/plain Message in there.
> > 
> > The best justification I could find for Anthony's expected output is in
> > the RFC 2046 BNF (see Appendix A):
> 
> I guess, in this case, my "expected output" is derived from pragmatism
> more than the RFC. I see these all too often, and it's always from
> broken mailers. I see absolutely no benefit to creating an empty
> text/plain in there. My driver for a lot of these tests was "what am
> I seeing in the wild?" Absolute strict conformance to the MIME rfcs,
> while a good thing in theory, should be secondary to producing the
> correct result.

Except that where the RFC defines things, it defines the expected
correct result.

In this particular instance though, I agree with you; the spec is far
from clear about what is "correct" so your interpretation is as good as
any, good enough for me, and what today's FeedParser implements.  

I was primarily looking for additional published material to reference
in comments.  Lacking that, we'll just do what we think is right (and I
agree with you here about not creating that extra empty text/plain).

-Barry