Re: [PATCH v2] ls-files: filter pathspec before lstat

[Jeff King <peff@peff.net>]

On Mon, Jun 08, 2026 at 07:37:15PM -0700, Tamir Duberstein wrote:

> +		/*
> +		 * match_pathspec() is linear in pathspec.nr, so prefilter only
> +		 * the single-pathspec case. Only entries shown by show_ce()
> +		 * satisfy --error-unmatch.
> +		 */
> +		if (pathspec.nr == 1 &&
> +		    !match_pathspec(repo->index, &pathspec, fullname.buf,
> +				    fullname.len, max_prefix_len, NULL,
> +				    S_ISDIR(ce->ce_mode) ||
> +				    S_ISGITLINK(ce->ce_mode)))
> +			continue;

This feels...kind of arbitrary, no? Surely it's also faster with
pathspec.nr == 2, and so on up to some nr closer to the size of the
total index. It feels weird to be making an arbitrary cutoff based on
pathspec performance in calling code like this.

It is not wrong, per se, as you are optimizing your case without trying
to hurt any others. But what do we do when somebody profiles it and
comes along trying to bump the number to 2, or 10?

I dunno.

-Peff