GNU bug report logs - #79036
[PATCH] Fix pdb tracking for remote filenames

Previous Next

Full log

Message #32 received at 79036 <at> debbugs.gnu.org (full text, mbox):

From: Liu Hui <liuhui1610 <at> gmail.com>
To: Eli Zaretskii <eliz <at> gnu.org>
Cc: 79036 <at> debbugs.gnu.org, kobarity <at> gmail.com, michael.albinus <at> gmx.de
Subject: Re: bug#79036: [PATCH] Fix pdb tracking for remote filenames
Date: Thu, 17 Jul 2025 21:30:01 +0800

On Thu, Jul 17, 2025 at 8:09 PM Eli Zaretskii <eliz <at> gnu.org> wrote:
>
> > From: Liu Hui <liuhui1610 <at> gmail.com>
> > Date: Thu, 17 Jul 2025 18:20:59 +0800
> > Cc: Michael Albinus <michael.albinus <at> gmx.de>, kobarity <kobarity <at> gmail.com>, 79036 <at> debbugs.gnu.org
> >
> > On Thu, Jul 17, 2025 at 4:46 PM Eli Zaretskii <eliz <at> gnu.org> wrote:
> >
> > > So now, Liu Hui, please explain the problem in more detail.
> > >
> > > I stared at the code for some time, and I don't understand why it goes
> > > to such great lengths here:
> > >
> > >   (let* ((file-name-prospect (concat (file-remote-p default-directory)
> > >                               file-name))
> > >          (file-buffer (get-file-buffer file-name-prospect)))
> > >     (unless file-buffer
> > >       (cond
> > >        ((file-exists-p file-name-prospect)
> > >         (setq file-buffer (find-file-noselect file-name-prospect)))
> > >        ((and (not (equal file-name file-name-prospect))
> > >              (file-exists-p file-name))
> > >         ;; Fallback to a locally available copy of the file.
> > >         (setq file-buffer (find-file-noselect file-name-prospect))))
> > >
> > > Why not just call find-file-noselect with FILE-NAME as its argument?
> > > The function find-file-noselect will itself check if there's already a
> > > buffer visiting that file, so it's unnecessary to do that "by hand"
> > > here.  And I don't see the reason for that 'concat' dance, either,
> > > since find-file-noselect again does everything that needs to be done
> > > internally.  So what am I missing here?
> >
> > Because file-name may be not the actual file. file-name is actually
> > extracted from the pdb output in the python shell, e.g.
> >
> >     >>> f()
> >     > /ssh:server:/tmp/test.py(3)f()
> >     (Pdb)
> >
> > Generally, pdb shows local file names. But if we send the code using
> > C-c C-c from python buffers (i.e. step 3), python-send-string passes
> > (buffer-file-name), which may be a remote file name, to python
> > process. Therefore, pdb may also shows remote file names.
> >
> > Then, if file-name is remote, we don't prepend any prefix (the updated
> > behavior in the patch) and calling find-file-noselect is enough.
>
> My question was why cannot we simply call find-file-noselect
> regardless of whether file-name is local or remote?  And why do we
> need all those checks with explicit calls to get-file-buffer etc.?

I have provided an example:

    >>> from test import f; f()
    > /tmp/test.py(3)f()
    -> return 1
    (Pdb)

Given above pdb output in the remote python shell, the file-name
"/tmp/test.py" is local and find-file-noselect will simply open the
local file. But the file is on the remote system.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.