Just a quick update (also answering my own question(s) below):

Regarding the status of this bug report: The fix for emacs-29 which was
initially intended to be emacs-29 only has (inadvertently?) found its way
to master. So I think we can close the report.

The discussion about the additional changes I made (I'm still working on
that s. below) could be moved elsewhere (emacs-devel?). Even though,
from my side there is no urgent need for that. I really appreciate the
feedback I got from Eli and hope to get some more.

> I've now added an additional patch which automatically handles unix/dos
> eol-types when downloading/uploading sieve scripts. So far, if a script
> downloaded from the server contained CRLF EOLs, the script buffer was
> full of '^M's. With the additional patch
> (0005-Autodetect-eol-type-of-sieve-manage-scripts), the EOL type is
> detected and used for decoding during script download (and subsequently
> also for encoding during upload).
> 
> For that, I changed the interface between 'sieve-upload' (in sieve.el),
> and 'manage-sieve-putscript' (plus 'sieve-manage-decode' and
> 'sieve-manage-send' in sieve-manage.el). Instead of transferring the
> script data as a string, the functions are now using the actual script
> buffer.
> 
> The eol-type detection is done in the new function
> 'sieve-manage--guess-buffer-coding-system'. But I would assume, that
> this functionality already exists somewhere else. E.g. 'find-file' must
> do a similar, much more detailed analysis. However, that seems to happen
> in the C implementation, so it's not directly usable in sieve-manage. Or
> am I missing something?

In the meantime, I found `detect-coding-region'/`detect-coding-string'
which in combination with `coding-system-eol-type' do exactly what I was
missing.


I've now started to refactor the encoding and sending functions in
sieve-manage.el with the intent to improve the readability and
testability of the code. I'm also adding some more tests. These
additional changes are in yet another patch
(0006-WiP-new-encode-tested-OK.patch).

I also added NEWS entries to patches 0002-Handle-BYE... and
0005-Autodetect-eol-type... (these were already present in the patches
of the previous mail).