GIT_DIR=. for hooks?

Hi there,

as it seems hooks (at least post-receive) are called with a $PWD in the
.git dir and GIT_DIR=. exported.

Now, that leads to problems when, say, diffing between the index and the
worktree ("Don't do that!", I know). Without cd'ing around, the worktree
is not found, and after "cd ..", the git-dir is not found.

I can unset GIT_DIR or set WORK_TREE, of course, but I'm wondering
whether GIT_DIR=. is a sane setting at all: a git-dir in $PWD is always
found, and when cd'ing away that setting does not help either.

Michael