On Wed, Jan 6, 2021 at 6:54 AM Derrick Stolee <stolee@xxxxxxxxx> wrote:
> On 1/5/2021 11:20 PM, Eric Sunshine wrote:
> > Is the behavior implemented by this patch desirable? That is, if the
> > user mistypes the name of the configuration variable, would it be
> > better to let the user know about the problem by returning an error
> > code rather than succeeding silently? Or do you foresee people
> > intentionally running the command against an empty config variable?
>
> As mentioned in the message, this is the situation the background
> maintenance would see if a user used 'git maintenance unregister' on
> all of their repos or removed the 'maintenance.repo' config values
> from their global config. I think it would be better to not start
> failing the background commands.
>
> Even outside of that context, we have no way to specify an "existing
> but empty" multi-valued config value over a non-existing config
> value. I'd rather prefer the interpretation "I succeeded in doing
> nothing" instead of "I think you made a mistake, because there's
> nothing to do."
>
> Could we meet in the middle and print a warning to stderr?
>
> warning(_("supplied config key '%s' has no values"));
>
> That would present a useful message to users running this command
> manually (or constructing automation) without breaking scripts
> that parse the output.
I don't know. My knee-jerk response is that such a warning could get
annoying quickly if this is used mostly in an automated environment,
and an empty config value is likely to come up in practice. In that
case, I'm somewhat negative on adding the warning. (I could perhaps
see a --dry-run or --verbose mode issuing the above warning, but
that's outside the scope of this series.)
> > Is the API of this command ideal? It feels odd to force the user to
> > specify required input via a command-line option rather than just as a
> > positional argument. In other words, since the config variable name is
> > mandatory, an alternative invocation format would be:
> >
> > git for-each-repo <config-var> <cmd>
> >
> > Or do you foresee future enhancements expanding the ways in which the
> > repo list can be specified (such as from a file or stdin or directly
> > via the command-line), in which case the `--config` option makes
> > sense.
>
> I believe some voice interest in specifying a list of repositories
> by providing a directory instead of a config value. That would
> require scanning the immediate subdirectories to see if they are Git
> repos.
>
> A --stdin option would also be a good addition, if desired.
>
> Since this command was intended for automation, not end-users, it
> seemed that future-proofing the arguments in this way would be a good
> idea. We want to remain flexible for future additions without
> breaking compatibility.
Fair enough.
