[PATCH 0/1] ref-filter.c: pass empty-string as NULL to atom parsers

[Taylor Blau <me@ttaylorr.com>]

Hi,

Attached is a one-long patch series to un-distinguish between atoms
without sub-arguments ("%(refname)") and atoms with empty sub-argument
lists ("%(refname:)").

This addresses a user-experience issue that Peff points out:

> Doh, that string_list behavior is what I was missing in my earlier
> comments. I agree this is probably the best way of doing it. I'm tempted
> to say that parse_ref_filter_atom() should do a similar thing. Right now
> we've got:
>
>   $ git for-each-ref --format='%(refname)' | wc
>      2206    2206   79929
>   $ git for-each-ref --format='%(refname:short)' | wc
>      2206    2206   53622
>   $ git for-each-ref --format='%(refname:)' | wc
>   fatal: unrecognized %(refname:) argument:
>       0       0       0

By treating %(refname) and %(refname:) as the same thing. Peff has
convinced me that these _are_ indeed the same thing, as the first is a
%(refname) atom without any sub-arguments, and the later is a %(refname)
%atom with empty sub-arguments.

The reasoning is highlighted in the comment this patch adds, which makes
more ergonomic the use of string_list_split in atom parser
implementations.

Thank you in advance :-).


--
- Taylor