Some PRETTY FORMATS format:<string> options don't work with git-archive export-subst $Format:$

> On Thu, Oct 09, 2014 at 12:42:39PM -0500, Derek Moore wrote:
>
>> As far as I've tested it would seem only %N doesn't resolve inside of
>> $Format:$, until I maybe do unit tests for this to identify any
>> others.
>
> Yes, %N is somewhat special in that the calling code needs to initialize
> the notes tree itself. We can't just do it lazily when we see the first
> %N because _which_ notes we show depends on other options (e.g., for
> log, if you've used --notes-ref, --show-notes=..., etc).
>
> So in theory you need something like 5b16360 (pretty: Initialize notes
> if %N is used, 2010-04-13), but adapted for git-archive. The trick,
> though, is that we do not even see the format string until we are
> looking at a particular file with a $Format$ marker. So you'd have to
> lazily initialize notes there (and if you want to support picking
> specific notes refs, you'd have to teach git-archive new options to do
> so[1]).
>
> Here's a quick-and-dirty patch that makes the snippet you posted earlier
> do what I think you expected. I haven't tested it beyond that, and am
> not planning to push it forward myself, but please feel free to use it
> as a basis for building a solution.
>
> ---
> diff --git a/archive.c b/archive.c
> index 952a659..3af781e 100644
> --- a/archive.c
> +++ b/archive.c
> @@ -5,6 +5,7 @@
>  #include "archive.h"
>  #include "parse-options.h"
>  #include "unpack-trees.h"
> +#include "notes.h"
>
>  static char const * const archive_usage[] = {
>         N_("git archive [options] <tree-ish> [<path>...]"),
> @@ -38,6 +39,8 @@ static void format_subst(const struct commit *commit,
>         if (src == buf->buf)
>                 to_free = strbuf_detach(buf, NULL);
>         for (;;) {
> +               struct userformat_want ufw = {0};
> +               struct strbuf notes = STRBUF_INIT;
>                 const char *b, *c;
>
>                 b = memmem(src, len, "$Format:", 8);
> @@ -50,10 +53,31 @@ static void format_subst(const struct commit *commit,
>                 strbuf_reset(&fmt);
>                 strbuf_add(&fmt, b + 8, c - b - 8);
>
> +               userformat_find_requirements(fmt.buf, &ufw);
> +               if (ufw.notes) {
> +                       static int initialized;
> +                       if (!initialized) {
> +                               init_display_notes(NULL);
> +                               initialized = 1;
> +                       }
> +                       format_display_notes(commit->object.sha1, &notes,
> +                                            get_log_output_encoding(), 1);
> +                       /*
> +                        * trim trailing newlines from note content, which is
> +                        * probably more appropriate for $Format$; should
> +                        * this actually remove internal newlines, too?
> +                        */
> +                       strbuf_rtrim(&notes);
> +               }
> +               ctx.notes_message = notes.buf;
> +
>                 strbuf_add(buf, src, b - src);
>                 format_commit_message(commit, fmt.buf, buf, &ctx);
>                 len -= c + 1 - src;
>                 src  = c + 1;
> +
> +               ctx.notes_message = NULL;
> +               strbuf_release(&notes);
>         }
>         strbuf_add(buf, src, len);
>         strbuf_release(&fmt);
>
> -Peff
>
> [1] I think you could get pretty far using `git -c core.notesRef=foo` to
>     give ad-hoc config, as the notes code should use that as the
>     ultimate default. But I didn't try it.