Re: [PATCH] format-patch: introduce format.outputDirectory configuration

[Jeff King <peff@peff.net>]

On Thu, Jun 18, 2015 at 04:13:23PM -0400, Jeff King wrote:

> > > You would also need to remove the "oh you gave me -o twice?" check,
> > > and change the semantics to "later -o overrides an earlier one",
> > > wouldn't you?  Otherwise you would never be able to override what
> > > you read from the config, I am afraid.
> > 
> > By the way, I actually think "later -o overrides an earlier one" is
> > a good change by itself, regardless of this new configuration.
> 
> Ah, I didn't realize we did that. Yeah, I think we should switch to
> "later overrides earlier". There is no need for "-o" to behave
> completely differently than all of our other options.

Much worse, though, is that we also have to interact with "--stdout". We
currently treat "--stdout -o foo" as an error; you need a separate
config_output_directory to continue to handle that (and allow "--stdout"
to override the config).

If I were designing from scratch, I would consider making "-o -" output
to stdout, and letting it override a previous "-o" (or vice versa). We
could still do that (and make "--stdout" an alias for that), but I don't
know if it is worth the trouble (it does change the behavior for anybody
who wanted a directory called "-", but IMHO it is more likely to save
somebody a headache than create one).

-Peff