Re: [PATCH] refs: add \t to reflog in the files backend

[Jeff King <peff@peff.net>]

On Fri, Jul 31, 2020 at 11:36:10AM +0000, Han-Wen Nienhuys via GitGitGadget wrote:

> diff --git a/refs.c b/refs.c
> index 89814c7be4..2dd851fe81 100644
> --- a/refs.c
> +++ b/refs.c
> @@ -907,7 +907,6 @@ static void copy_reflog_msg(struct strbuf *sb, const char *msg)
>  	char c;
>  	int wasspace = 1;
>  
> -	strbuf_addch(sb, '\t');
>  	while ((c = *msg++)) {
>  		if (wasspace && isspace(c))
>  			continue;
> diff --git a/refs/files-backend.c b/refs/files-backend.c
> index e0aba23eb2..985631f33e 100644
> --- a/refs/files-backend.c
> +++ b/refs/files-backend.c
> @@ -1628,8 +1628,10 @@ static int log_ref_write_fd(int fd, const struct object_id *old_oid,
>  	int ret = 0;
>  
>  	strbuf_addf(&sb, "%s %s %s", oid_to_hex(old_oid), oid_to_hex(new_oid), committer);
> -	if (msg && *msg)
> +	if (msg && *msg) {
> +		strbuf_addch(&sb, '\t');
>  		strbuf_addstr(&sb, msg);
> +	}

I wondered here whether the existing code would always write the tab,
even for an entry with no message, since we seem to unconditionally add
the tab in the hunk above.

But it looks like we only call copy_reflog_msg() if it's non-empty:

  static char *normalize_reflog_message(const char *msg)
  {
          struct strbuf sb = STRBUF_INIT;
  
          if (msg && *msg)
                  copy_reflog_msg(&sb, msg);
          return strbuf_detach(&sb, NULL);
  }

so this is retaining that behavior (and indeed, doing a simple "git
update-ref" confirms that we currently omit the tab in this case).

So the patch looks good (and the intent seems obviously good to me, as
well).

-Peff