[MlMt] Bug in preserving format=flowed text from external editors?

[Philip Paeps]

On 2017-04-18 10:19:51 (+0200), Benny Kjær Nielsen 
<mailinglist at freron.com> wrote:
> On 11 Apr 2017, at 13:36, Philip Paeps wrote:
>> MailMate seems to be better at preserving trailing whitespace in 
>> replies than in new messages, if that helps.
>
> I think this is because MailMate only strips “extraneous” 
> whitespace from non-quoted text.

I can confirm that this is what appears to happen.  Text coming in from 
the external editor is left alone if it's quoted but stripped of 
trailing whitespace otherwise.

>> For instance: I typed this message in Vim but the only way to get the 
>> flowed format was to remove hard line breaks in MailMate.
>>
>> Is there a way to configure MailMate not to strip trailing whitespace 
>> from buffers messages edited externally?  Or perhaps to debug its 
>> behaviour when it gets the rewrapping wrong?
>
> I haven't changed anything related to `format=flowed` and external 
> editors.

It took me a long time to notice something was going on. :)

> The problem is that MailMate does not expect you to return 
> `format=flowed` text. MailMate only considers `format=flowed` to be a 
> technique used to “encode” text before sending. And received 
> `format=flowed` text is “decoded” before being used in the text 
> editor (both built-in and external). In other words, you should never 
> hard-wrap the lines of a paragraph -- or if you do then your text 
> editor must unwrap them before saving.

Would it be possible to add a setting to MailMate to leave text from an 
external editor alone?  `MmTrustExternalEditor` perhaps? :)

I noticed MailMate's behaviour when I was composing an email with 
sections that had to be hard-wrapped (code fragments) and sections that 
needed to flow (surrounding context).  The `format=flowed` format allows 
for this: terminate lines that should be fixed with `CRLF` and lines 
that should be flowed with `SP CRLF`.  (I could have used Markdown but 
the mailing list I was sending it to is picky about that).

I realise that this is probably not a very common use-case.  I can just 
write picky mails in Mutt.  It doesn't actually come up all that much.

(Aside: if you find yourself near the external editor code, it would 
also be helpful if MailMate could have a setting to pass headers to and 
from the external editor.)

> You might have noticed that MailMate seems to use `format=flowed` for 
> quoted text in its internal editor, but this is a *hack* in order to 
> be able to prefix `>` visually. If you resize the window then these 
> lines are actually reflowed. (Maybe some day I'll find a better way to 
> do that.)

Hah - I hadn't noticed.  I don't tend to resize windows much.  Nice 
trick! :)

> It looks particularly bad if using a proportional font when editing, 
> but I do recommend fixed width fonts in the Composer (for readability 
> while editing). (The editor font is not used for outgoing emails.)

I use a fixed-width font. :)

Philip

-- 
Philip Paeps
Senior Reality Engineer
Ministry of Information