Re: [PATCH 0/8] Add 'ls-files --json' to dump the index in json

[Johannes Schindelin <Johannes.Schindelin@gmx.de>]

Hi Peff,

On Fri, 21 Jun 2019, Jeff King wrote:

> On Fri, Jun 21, 2019 at 03:16:52PM +0200, Johannes Schindelin wrote:
>
> > > I think your warning in the manpage that this is for debugging is fine,
> > > as it does not put us on the hook for maintaining the feature nor its
> > > format forever. We might want to call it "--debug=json" or something,
> > > though, in case we do want real stable json support later (though of
> > > course we would be free to steal the option then, since we're making no
> > > promises).
> >
> > Traditionally, we have not catered well to 3rd-party applications in Git,
> > and this JSON format would provide a way out of that problem.
> >
> > So I would like *not* to lock the door on letting this feature stabilize
> > organically.
>
> I'd like it to stabilize organically, too, but my thinking was that we'd
> wait a while and then promote it to a stable name eventually.

Git's command-line options have stabilized organically.

Example: to include untracked files in `git stash`, use `-u` or
`--include-untracked`, to include them in `git add`, use `-A` or `--all`,
to include them in `git grep`, use `--untracked` (no short option), to
include them in `git ls-files`, use `-o` or `--others`. The command `git
commit` does not even have an option to include untracked files.

You know of more examples of organically grown designs in Git, I am sure.
Given those examples, I am not sure that I want the JSON format to
stabilize organically.

> > I'd be much more in favor of `--json[=<version>]`, with an initial
> > version of 0 to indicate that it really is unstable for now.
>
> That's OK with me, too, if you think "0" indicates that sufficiently
> (we've used "v0" in a lot of other places to refer to stable protocols,
> like the git:// one). Maybe it's OK with some documentation making it
> clear.

I did think that the `0` would be clear, but you are probably right.

> I'm not sure whether we want to be locked into supporting this v0
> forever or not (though maybe it would not be such a burden).
>
> I think JSON-based output also has the potential to need fewer bumps.
> It's syntactically stable, so it's really just about our schema. And
> it's easy to say "newer versions of Git may produce new keys; you can
> ignore them", as long as we do not change the meaning of existing keys.
> That might be an easier promise to make.

Right.

Thanks,
Dscho