Re: [PATCH] diffcore-pickaxe: simplify has_changes and contains

From: Jeff King <peff@peff.net>
Date: Jul 7, 2013, 04:03 UTC
Message-ID: <20130707040337.GA30898@sigill.intra.peff.net>
In-Reply-To: <1373118807-1345-1-git-send-email-rene.scharfe@lsrfire.ath.cx>

On Sat, Jul 06, 2013 at 03:53:27PM +0200, René Scharfe wrote:

> Halve the number of callsites of contains() to two using temporary
> variables, simplifying the code.  While at it, get rid of the
> diff_options parameter, which became unused with 8fa4b09f.

There is a slight change in behavior, too:

Show 8 quoted lines

> -	if (!one)
> -		return contains(two, o, regexp, kws) != 0;
> -	if (!two)
> -		return contains(one, o, regexp, kws) != 0;
> -	return contains(one, o, regexp, kws) != contains(two, o, regexp, kws);
> +	unsigned int one_contains = one ? contains(one, regexp, kws) : 0;
> +	unsigned int two_contains = two ? contains(two, regexp, kws) : 0;
> +	return one_contains != two_contains;

Before, if (!one && !two) we would call contains(two, ...), and now we will simply assume it is zero. Which I think is an improvement, as we would have segfaulted before. I don't think it is a bug in the current code (we would not ever feed the function two NULLs), but it is nice to be more defensive.

Acked-by: Jeff King <peff@peff.net>

-Peff