bug#65979: incorrect “guix hash” for FastQC

["Ludovic Courtès" <ludo@gnu.org>]

(Oops, now I see you had already found the reason.)

Simon Tournier <zimon.toutoune@gmail.com> skribis:

> What do we fix?  The procedure vcs-file? or fixed-output computation?

There are two things are:

  1. ‘vcs-file?’, used by ‘guix hash -rx’;

  2. ‘git-fetch’, which does (delete-file-recursively ".git").

Clearly #2 is correct (it’s perfectly fine to have a ‘.svn’ directory in
a Git repo), whereas #1 is an approximation that, in corner cases like
this one, gives the wrong answer.

My take is that it’s OK to keep ‘vcs-file?’ as is: the best we could do
would be to add complicated heuristics in the hope corner cases like
this one would be better dealt with, but it wouldn’t be bullet-proof
anyway.

WDYT?

Ludo’.