Re: Re: Using babel to generate a commit log

[Nick Dokos <nicholas.dokos@hp.com>]

Luke Crook <luke@balooga.com> wrote:

> Jambunathan K <kjambunathan <at> gmail.com> writes:
> 
> > 
> > Luke Crook <luke <at> balooga.com> writes:
> > 
> > >   2) I have to add at delay of at least 5 seconds (set-for 5 t) as vc-git 
> calls 
> > > "git log" as an asynchronous process. If not for the delay then babel 
> > > immediately returns an empty buffer and the "vc-call-backend" process never 
> > > completes.
> > >
> > > Is there a better way that I can accomplish (2) ?
> > 
> > Quick hints if you are willing to settle for some hacks.
> > 
> > In vc-do-command, you may have to set OKSTATUS to 0. Track
> > `vc-disable-async-diff' in vc.el and vc-svn.el for possible hints.
> > 
> 
> I changed my code to wait until the 'Git' process completes. Luckily "vc-call-
> backend" returns the async process.
> 
Oh, I missed that - thanks for pointing it out.

> #+begin_src emacs-lisp :var limit="" :file test.log :exports results
> ;; Most of this code is copied from vc.el vc-print-log
> (when (vc-find-backend-function (vc-backend (buffer-file-name (current-buffer)))
>   				                'print-log)
>       (let* ((limit (if (numberp limit) limit vc-log-show-limit))
> 	         (vc-fileset (vc-deduce-fileset t)) ;FIXME: Why t? --Stef
> 	         (backend (car vc-fileset))
> 	         (files (cadr vc-fileset)))
> 	  (with-temp-buffer 
>           (let ((status (vc-call-backend backend
> 	      		                     'print-log
> 	      		                     files
> 	      		                     (current-buffer))))
>           (while (not (eq 'exit (process-status status)))
>               (sit-for 1 t))
>           (buffer-string)))))
> #+end_src
> 

... or you could use a sentinel :-)

One bit of defensive programming might be to check that status *is* a
process before you do the wait: vc-do-command returns a real status in
the synchronous case, so if you cut-n-paste this code with some other
command that does not use async, it'll blow up.

Nick