# [PATCH] filter-branch: Export variable `workdir' for --commit-filter

2 messages from 2011-08-07 to 2011-08-08. Participants: Michael Witten, Junio C Hamano.
Thread: https://gitlist.dev/t/28035

## Michael Witten, 2011-08-07 02:03

Subject: [PATCH] filter-branch: Export variable `workdir' for --commit-filter
Message-ID: <f06dd070abcc485e98c054ec3ee298f9-mfwitten@gmail.com>
URL: https://gitlist.dev/e/f06dd070abcc485e98c054ec3ee298f9-mfwitten%40gmail.com

```
According to `git help filter-branch':

       --commit-filter <command>
           ...
           You can use the _map_ convenience function in this filter,
           and other convenience functions, too...
           ...

However, it turns out that `map' hasn't been usable because it depends
on the variable `workdir', which is not propogated to the environment
of the shell that runs the commit-filter <command> because the
shell is created via a simple-command rather than a compound-command
subshell:

 @SHELL_PATH@ -c "$filter_commit" "git commit-tree" \
                 $(git write-tree) $parentstr < ../message > ../map/$commit ||
                         die "could not write rewritten commit"

One solution is simply to export `workdir'. However, it seems rather
heavy-handed to export `workdir' to the environments of all commands,
so instead this commit exports `workdir' for only the duration of the
shell command in question:

 workdir=$workdir @SHELL_PATH@ -c "$filter_commit" "git commit-tree" \
                 $(git write-tree) $parentstr < ../message > ../map/$commit ||
                         die "could not write rewritten commit"

Signed-off-by: Michael Witten <mfwitten@gmail.com>
---
 git-filter-branch.sh |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/git-filter-branch.sh b/git-filter-branch.sh
index 962a93b..6b5f225 100755
--- a/git-filter-branch.sh
+++ b/git-filter-branch.sh
@@ -363,7 +363,7 @@ while read commit parents; do
 	sed -e '1,/^$/d' <../commit | \
 		eval "$filter_msg" > ../message ||
 			die "msg filter failed: $filter_msg"
-	@SHELL_PATH@ -c "$filter_commit" "git commit-tree" \
+	workdir=$workdir @SHELL_PATH@ -c "$filter_commit" "git commit-tree" \
 		$(git write-tree) $parentstr < ../message > ../map/$commit ||
 			die "could not write rewritten commit"
 done <../revs
-- 
1.7.6.134.gcf13f6

```

## Junio C Hamano, 2011-08-08 19:11

Subject: Re: [PATCH] filter-branch: Export variable `workdir' for --commit-filter
Message-ID: <7vzkjjwvuk.fsf@alter.siamese.dyndns.org>
URL: https://gitlist.dev/e/7vzkjjwvuk.fsf%40alter.siamese.dyndns.org
In-Reply-To: <f06dd070abcc485e98c054ec3ee298f9-mfwitten@gmail.com>

```
Michael Witten <mfwitten@gmail.com> writes:

> According to `git help filter-branch':
>
>        --commit-filter <command>
>            ...
>            You can use the _map_ convenience function in this filter,
>            and other convenience functions, too...
>            ...
>
> However, it turns out that `map' hasn't been usable because it depends
> on the variable `workdir', which is not propogated to the environment
> of the shell that runs the commit-filter <command>...

Thanks.

```