On Sun, Feb 14 2021, René Scharfe wrote:
> +'%(describe)':: human-readable name, like linkgit:git-describe[1];
> + empty string for undescribable commits
In the case of undescribable we've got the subcommand exiting non-zero
and we ignore it. The right thing in this case given how the rest of
format arguments work, but maybe something to explicitly test for?
>
> + if (skip_prefix(placeholder, "(describe)", &arg)) {
> + struct child_process cmd = CHILD_PROCESS_INIT;
> + struct strbuf out = STRBUF_INIT;
> + struct strbuf err = STRBUF_INIT;
> +
> + cmd.git_cmd = 1;
> + strvec_push(&cmd.args, "describe");
> + strvec_push(&cmd.args, oid_to_hex(&commit->object.oid));
> + pipe_command(&cmd, NULL, 0, &out, 0, &err, 0);
> + strbuf_rtrim(&out);
> + strbuf_addbuf(sb, &out);
> + strbuf_release(&out);
> + strbuf_release(&err);
> + return arg - placeholder;
> + }
There's another edge case in this: if you do "%(describe)%(describe)"
it'll be run twice for the rev, 3 times if you add another "%(describe)"
etc. I don't know if pretty.c has an easy way to cache/avoid that.
