[PATCH] mail: encode long unicode lines in emails properly (issue5687)

[Yuya Nishihara]

On Mon, 25 Sep 2017 10:06:44 +0300, Igor Ippolitov wrote:
> I dug a little more and finally realized, that the patch will work nicely
> in python 3.6.
> The compat3.2 we discussed in IRC is not a module, but API which is in the
> class
> This api includes set_payload and set_charset methods. So nothing will be
> broken
> 
> Additionally, I tested that initial issue with long lies is not solved, so
> you have to
> perform some additional checks encoding the body (so there is no 'simple'
> solution)
> 
> In the end, I belive, the patch submitted is the best solution for now:
> It solves all issues and does minimal changes.

Okay, thanks for investigating that.

> >> >          if len(line) > 950:
> >> >              body = quopri.encodestring(body)
> >> > -            enc = "quoted-printable"
> >> > +            cs.body_encoding = email.charset.QP
> >>
> >> Perhaps body_encoding should be preserved if it's set to BASE64. IIUC,
> >> BASE64
> >> is preferred for utf-8 content.

Any thought on this? Do you think QP is preferred for UTF-8 over the default
BASE64 encoding?

> >> > +            enc = True
> >> >              break
> >> > +    if enc:
> >> > +        msg.set_charset(cs)
> >> > +        msg.set_payload(body)
> >> > +    else:
> >> > +        msg.set_payload(body)
> >> > +        msg.set_charset(cs)
> >>
> >> This if/else seems unnecessary if body is not encoded beforehand.

Can you fix this? IIUC, we can just call msg.set_payload(body, charset) if
body isn't encoded in QP manually.