Re: [O] [BUG] bug in org-publish and a (wrong) patch

[Nick Dokos]

David Maus <address@hidden> wrote:

> At Fri, 08 Apr 2011 12:58:06 -0400,
> Nick Dokos wrote:
> >
> > Carsten Dominik <address@hidden> wrote:
> >
> > > Hi Nick,
> > >
> > > I have not looked closely, but maybe you can use
> > >
> > >
> > > (expand-file-name  .... (file-name-directory filename))
> > >
> > > to fix this patch?  Not sure, I have not spent any time on it.
> > >
> >
> > Almost but not quite: C-h v expand-file-name says
> >
> > ,----
> > | (expand-file-name NAME &optional DEFAULT-DIRECTORY)
> > |
> > | Convert filename NAME to absolute, and canonicalize it.
> > | Second arg DEFAULT-DIRECTORY is directory to start with if NAME is 
> > relative
> > | (does not start with slash or tilde); if DEFAULT-DIRECTORY is nil or 
> > missing,
> > | the current buffer's value of `default-directory' is used.
> > `----
> >
> > so you end up tacking it onto a completely unrelated directory (and my
> > experiments confirm this).
> >
> > But there is a :base-directory for the project that could be obtained
> > from the project-plist and passed to expand-file-name.  I think that
> > would work but would require passing the project-plist down through a couple
> > of layers to org-publish-cache-ctime-of-src. Alternatively, it (or just
> > the base directory) could be bound dynamically in org-publish-file and
> > used in the ctime function.
> >
> > What do you think would be preferable?
> 
> Took some time, but attached patch fixes the problem w/o the need for
> passing down :base-directory at all. Simply expand-filename only if
> the symlink is relative; luckily the filename passed to this fun
> already is absolute.
> 
> @Bastien: Didn't push because I assume you already started the release
> process for Org 7.6.
> 

> From f6ed4d5707995f34a627886d0607dd7e6343144b Mon Sep 17 00:00:00 2001
> From: David Maus <address@hidden>
> Date: Sun, 26 Jun 2011 20:02:42 +0200
> Subject: [PATCH] Properly handle relative symlinks when publishing
> 
> * org-publish.el (org-publish-cache-ctime-of-src): Properly handle
> relative symlinks.
> 
> At Thu, 07 Apr 2011 01:11:00 -0400,
> Nick Dokos wrote:
> >
> > org-publish-cache-ctime-of-src tries (but does not always succeed) to
> > deal with symlinks: file-symlink-p returns the target as a string, but
> > if the target is relative to the symlink, that's not going to fly.
> > e.g. if c is a symlink like this
> >
> >     /a/b/c->../d/f
> >
> > then (file-symlink-p "/a/b/c") -> "../d/f"
> > but if the current directory is any place other than /a/b, the target
> > will not be found, the file attributes are going to be nil and
> > the function will blow up.
> ---
>  lisp/org-publish.el |    7 ++++---
>  1 files changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/lisp/org-publish.el b/lisp/org-publish.el
> index 56cc80a..0d3d70a 100644
> --- a/lisp/org-publish.el
> +++ b/lisp/org-publish.el
> @@ -1157,9 +1157,10 @@ Returns value on success, else nil."
>  
>  (defun org-publish-cache-ctime-of-src (filename)
>    "Get the FILENAME ctime as an integer."
> -  (let ((src-attr (file-attributes (if (stringp (file-symlink-p filename))
> -                                    (file-symlink-p filename)
> -                                  filename))))
> +  (let* ((symlink-maybe (or (file-symlink-p filename) filename))
> +      (src-attr (file-attributes (if (file-name-absolute-p symlink-maybe)
> +                                     symlink-maybe
> +                                   (expand-file-name symlink filename)))))
>      (+
>       (lsh (car (nth 5 src-attr)) 16)
>       (cadr (nth 5 src-attr)))))
> -- 
> 1.7.2.5
> 

I don't think it's correct as it stands: What is ``symlink'' on the last
line?  should it be be symlink-maybe perhaps? and expand-file-name
expands wrt to the default directory passed as its third argument. Maybe
the third argument can be (file-name-directory filename) as Carsten
suggested, but surely it cannot be just ``filename''.

Replacing the last line with

          (expand-file-name symlink-maybe (file-name-directory filename))...

my (very simple) test case gets published correctly, so it's
certainly better than what's there.

Nick