Re: [PATCH] Move worktree setup out of setup_git_directory*

>   - At startup:
>
>    - If the command always need to run from a repository, call
>      setup_git_directory(), which would complain and die if you
>      are outside.
>
>    - If the command can optionally run in a repository, use
>      setup_git_directory_gently(&nongit_ok); it won't complain
>      but sets nongit_ok to true if run outside a repository.
>
>    In either case, they return prefix string to be used for
>    setup_work_tree() later.
>
>    In either case, there is no chdir() done at this point.

>   - After calling setup_git_directory(), or you made sure you are
>    in a repository after callilng setup_git_directory_gently(),
>    call setup_work_tree().  This will chdir to the top of the
>    work tree.
>
>   - When you need to know where $GIT_DIR is, call get_git_dir().
>    When you need to know where the work tree is, call
>    get_git_work_tree().  However, it is an error to call these
>    functions before calling setup_git_directory and
>    setup_work_tree.