Re: [PATCH v19 1/2] refactor format_branch_comparison in preparation

> +static void format_branch_comparison(struct strbuf *sb,
> +				     bool up_to_date,
> +				     int ours, int theirs,
> +				     const char *branch_name,
> +				     enum ahead_behind_flags abf,
> +				     bool show_divergence_advice)
> +{
> +	if (up_to_date) {
>  		strbuf_addf(sb,
>  			_("Your branch is up to date with '%s'.\n"),
> -			base);
> +			branch_name);
>  	} else if (abf == AHEAD_BEHIND_QUICK) {
>  		strbuf_addf(sb,
>  			    _("Your branch and '%s' refer to different commits.\n"),
> -			    base);
> +			    branch_name);
>  		if (advice_enabled(ADVICE_STATUS_HINTS))
>  			strbuf_addf(sb, _("  (use \"%s\" for details)\n"),
>  				    "git status --ahead-behind");

> +/*
> + * Return true when there is anything to report, otherwise false.
> + */
> +int format_tracking_info(struct branch *branch, struct strbuf *sb,
> +			 enum ahead_behind_flags abf,
> +			 int show_divergence_advice)
> +{
> +	int ours, theirs, sti;
> +	const char *full_base;
> +	char *base;
> +	int upstream_is_gone = 0;
> +
> +	sti = stat_tracking_info(branch, &ours, &theirs, &full_base, 0, abf);
> +	if (sti < 0) {
> +		if (!full_base)
> +			return 0;
> +		upstream_is_gone = 1;
> +	}
> +
> +	base = refs_shorten_unambiguous_ref(get_main_ref_store(the_repository),
> +					    full_base, 0);
> +
> +	if (upstream_is_gone) {
> +		strbuf_addf(sb,
> +			_("Your branch is based on '%s', but the upstream is gone.\n"),
> +			base);
> +		if (advice_enabled(ADVICE_STATUS_HINTS))
> +			strbuf_addstr(sb,
> +				_("  (use \"git branch --unset-upstream\" to fixup)\n"));
> +	} else {
> +		format_branch_comparison(sb, !sti, ours, theirs, base, abf, show_divergence_advice);
> +	}
> +
>  	free(base);
>  	return 1;
>  }