Re: [PATCH v5 1/4] git: make super-prefix option

> On Wed, Sep 28, 2016 at 02:50:40PM -0700, Brandon Williams wrote:
> 
> > Add a super-prefix environment variable 'GIT_INTERNAL_SUPER_PREFIX'
> > which can be used to specify a path from above a repository down to its
> > root.  The immediate use of this option is by commands which have a
> > --recurse-submodule option in order to give context to submodules about
> > how they were invoked.  This option is currently only allowed for
> > builtins which support a super-prefix.
> 
> What about non-builtins?
> 
> E.g., what should
> 
>   git --super-prefix=foo bar
> 
> do? Should the externals and scripts check the presence of
> GIT_INTERNAL_SUPER_PREFIX and barf if it is set? Most scripts would
> probably notice eventually when calling some other builtin that doesn't
> support SUPER_PREFIX, but it seems hacky to count on that.
> 
> There's also the question of 3rd-party programs. If we want to be
> conservative, I think you'd want to just always bail in
> execv_dashed_external() if --super-prefix is in use. That doesn't give
> an option for scripts to say "hey, I support this", but we can perhaps
> worry about loosening later.
> 
> -Peff