bug#1408: 23.0.60; git/*vc-dir*: does not register a symbolic link which befor was a directory with one singel file

[Dan Nicolaescu <dann@ics.uci.edu>]

severity 1408 wishlist
quit


Gregor Zattler <telegraph@gmx.net> writes:

  > Disclaimer: I'm new to version control, perhaps I do not understand
  > the situation.  These are the steps to reproduce the problem:
  > 
  > $ mkdir vc-emacs-test
  > $ cd vc-emacs-test
  > $ git init
  > Initialized empty Git repository in /tmp/vc-emacs-test/.git/
  > $ mkdir dir directory
  > $ echo test >dir/test
  > $ git add .
  > $ git commit -a -m "one"
  > Created initial commit cdd09ae: one
  >  1 files changed, 1 insertions(+), 0 deletions(-)
  >  create mode 100644 dir/test
  > $ rm -rf dir
  > $ ln -s directory dir
  > $ emacs-snapshot -Q
  > 
  > ^X v d
  > 
  > now in buffer *vc-dir* looks like this:
  > 
  > 
  > VC backend : Git
  > Working dir: /tmp/vc-emacs-test/
  > Branch     : master
  > 
  >                           ./
  >      unregistered         dir
  >                           dir/
  >      removed              dir/test
  > 
  > 
  > move cursor on this line type 'i' to register.  Following error
  > messages are displayed:
  > 
  > on the last line, copied from *Messages*:
  > vc-do-command: Running git update-index --add -- dir...FAILED (status 128)
  > 
  > 
  > In buffer *vc*:
  > 
  > error: 'dir' appears as both a file and as a directory
  > error: dir: cannot add to the index - missing --add option?
  > fatal: Unable to process path dir
  > 
  > 
  > 
  > 
  > I think this is a bug because emacs should handle this case (at least
  > with a sensible message what to do).
  > 
  > Actually this happend in a "real" scenario, I decided to reproduce a
  > minimalistic example. 

VC is not really prepared to deal with arbitrary commands on symlinks,
so it's not surprising that this corner case fails.
Changing a directory into a symlink between to VC operations is not
something that happens very frequently...