Re: [PATCH v2 02/38] rename_ref_available(): add docstring

> +/*
> + * Check whether an attempt to rename old_refname to new_refname would
> + * cause a D/F conflict with any existing reference (other than
> + * possibly old_refname). If there would be a conflict, emit an error
> + * message and return false; otherwise, return true.
> + *
> + * Note that this function is not safe against all races with other
> + * processes (though rename_ref() catches some races that might get by
> + * this check).
> + */
> +int rename_ref_available(const char *old_refname, const char *new_refname);