From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff King Subject: Re: [BUG] redundant error message Date: Thu, 5 Dec 2013 16:00:00 -0500 Message-ID: <20131205210000.GA19617@sigill.intra.peff.net> References: <20131205191518.GB19039@sigill.intra.peff.net> <20131205200306.GA13443@sigill.intra.peff.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: Duy Nguyen , Git Mailing List To: Junio C Hamano X-From: git-owner@vger.kernel.org Thu Dec 05 22:00:07 2013 Return-path: Envelope-to: gcvg-git-2@plane.gmane.org Received: from vger.kernel.org ([209.132.180.67]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1Vog1n-0002Wt-CP for gcvg-git-2@plane.gmane.org; Thu, 05 Dec 2013 22:00:07 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751500Ab3LEVAD (ORCPT ); Thu, 5 Dec 2013 16:00:03 -0500 Received: from cloud.peff.net ([50.56.180.127]:51198 "HELO peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1750924Ab3LEVAC (ORCPT ); Thu, 5 Dec 2013 16:00:02 -0500 Received: (qmail 1694 invoked by uid 102); 5 Dec 2013 21:00:02 -0000 Received: from c-71-63-4-13.hsd1.va.comcast.net (HELO sigill.intra.peff.net) (71.63.4.13) (smtp-auth username relayok, mechanism cram-md5) by peff.net (qpsmtpd/0.84) with ESMTPA; Thu, 05 Dec 2013 15:00:02 -0600 Received: by sigill.intra.peff.net (sSMTP sendmail emulation); Thu, 05 Dec 2013 16:00:00 -0500 Content-Disposition: inline In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Thu, Dec 05, 2013 at 12:15:07PM -0800, Junio C Hamano wrote: > >> Hmph, it looks like it is following the usual "zero-or-more dashed > >> options, zero-or-more revs and then zero-or-one double-dash and then > >> zero-or-more paths" rule to parse the thing. "foobar" is a file and > >> not a rev, so "--" should not be there, no? > >> > >> Confused why you think it is not right... > > > > Because once you say "--", then all ambiguity goes away, no? > > But it is tricky (not from implementation but from semantics point > of view) to make rev-parse follow that "-- separates revs and paths" > rule literally. The primary use of rev-parse is to convert revs in > extended SHA-1 expressions into concrete object names, so that > scripts do not have to worry about having to deal with object names > in a format that is not 40-hexdecimal. "git rev-parse foobar --" > that gives > > foobar > -- > > without any error, because 'foobar' cannot be made into an object > name, would be behaving in a way unexpected by the calling script, > no? Yes, I do expect an error. But it should not be "-- after filename". It should be "foobar is not a revision". Thinking on it more, though, the problem is purely limited to wrong error messages. If "foobar" exists as a rev, we do parse it correctly. If it does not, we are in the wrong code path, but it _must_ be an error at that point (either because foobar does not exist as a file, or it does and has "--" after it). It would be nice to get the error messages right, though. I do not see any reason why it could not follow the same steps as "git log", converting revisions (or throwing an error as appropriate) on the left side of the "--", and passing through the right side untouched. -Peff