Re: [PATCH] rebase: exec leaks GIT_DIR to environment

> Hi Jake,
>
> On Fri, 27 Oct 2017, Jacob Keller wrote:
>
>> From: Jacob Keller <jacob.keller@gmail.com>
>>
>> I noticed a failure with git rebase interactive mode which causes "exec"
>> commands to be run with GIT_DIR set. When GIT_DIR is in the environment,
>> then any command which results in running a git command in
>> a subdirectory will fail because GIT_DIR=".git".
>>
>> This unfortunately breaks one of my project's Makefiles, which uses
>> git-describe to find the version information, but does so from within
>> a sub directory.
>>
>> I'm in the process of running a bisect to find where this got
>> introduced, but I suspect it's part of the rebase--helper changes that
>> happened a while ago.
>
> A safe assumption. I do not know how the shell code managed that GIT_DIR
> reset, though:
>
> -- snip from v2.12.0's git-rebase--interactive.sh --
>         x|"exec")
>                 read -r command rest < "$todo"
>                 mark_action_done
>                 eval_gettextln "Executing: \$rest"
>                 "${SHELL:-@SHELL_PATH@}" -c "$rest" # Actual execution
> -- snap --
>

> - your added test tries to remove the directory with -ff instead of -rf
>
> - it tries to run `git rebase --abort` afterwards, which fails with my fix
>   because there is no rebase in progress
>
> - instead of `cd subdir && ...`, it calls `>cd subdir && ...`, which
>   causes it to abort with a "subdir: not fonud"
>

>
> I only had time to write these two patches, and to verify that t3404
> passes now, but not that anything else passes, neither to write a proper
> commit message.
>
> Maybe you can take it from there?
>