From mboxrd@z Thu Jan 1 00:00:00 1970 From: Junio C Hamano Subject: Re: [PATCH 3/3] implement pattern matching in ce_path_match Date: Thu, 15 Jan 2009 18:51:07 -0800 Message-ID: <7vzlhsneuc.fsf@gitster.siamese.dyndns.org> References: <1231944876-29930-1-git-send-email-drizzd@aon.at> <1231944876-29930-2-git-send-email-drizzd@aon.at> <1231944876-29930-3-git-send-email-drizzd@aon.at> <1231944876-29930-4-git-send-email-drizzd@aon.at> <7vljtd20m6.fsf@gitster.siamese.dyndns.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: git@vger.kernel.org, johannes@familieschneider.info To: Clemens Buchacher X-From: git-owner@vger.kernel.org Fri Jan 16 03:52:46 2009 Return-path: Envelope-to: gcvg-git-2@gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1LNep7-0001C2-Pi for gcvg-git-2@gmane.org; Fri, 16 Jan 2009 03:52:42 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754426AbZAPCvR (ORCPT ); Thu, 15 Jan 2009 21:51:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754269AbZAPCvR (ORCPT ); Thu, 15 Jan 2009 21:51:17 -0500 Received: from a-sasl-quonix.sasl.smtp.pobox.com ([208.72.237.25]:37164 "EHLO sasl.smtp.pobox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754162AbZAPCvQ (ORCPT ); Thu, 15 Jan 2009 21:51:16 -0500 Received: from localhost.localdomain (unknown [127.0.0.1]) by b-sasl-quonix.sasl.smtp.pobox.com (Postfix) with ESMTP id 90FD11CA26; Thu, 15 Jan 2009 21:51:14 -0500 (EST) Received: from pobox.com (unknown [68.225.240.211]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by b-sasl-quonix.sasl.smtp.pobox.com (Postfix) with ESMTPSA id C33661CA2A; Thu, 15 Jan 2009 21:51:09 -0500 (EST) In-Reply-To: <7vljtd20m6.fsf@gitster.siamese.dyndns.org> (Junio C. Hamano's message of "Wed, 14 Jan 2009 10:39:29 -0800") User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) X-Pobox-Relay-ID: 8A3CF83C-E378-11DD-A4D9-2E3B113D384A-77302942!a-sasl-quonix.pobox.com Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Junio C Hamano writes: > Clemens Buchacher writes: > >> With this patch ce_path_match uses match_pathspec in order to perform >> pattern matching. > > We have two conflicting definitions of pattern matching in our system. > I'd make it more explicit which kind of pattern matching you are talking > about here. > > The family of operations based on the diff-tree machinery (e.g. path > limited revision walking "git log A..B -- dir1/dir2") define the pattern > matching as "leading path match (exact match is just a special case of > this)". Other operations that work on paths in the work tree and the > index (e.g. grep, ls-files) uses "leading path match, but fall back to > globbing". > > In the longer term we really should unify them by teaching the former to > fall back to globbing without getting undue performance hit, and this > patch may be a step in the right direction. There are optimizations that > assume the "leading path" semantics to trim the input early and avoid > opening and descending into a tree object if pathspec patterns cannot > possibly match (see tree-diff.c::tree_entry_interesting() for an example), > and we need to teach them to notice a glob wildcard in an earlier part of > a pathspec and to descend into some trees that they would have skipped > with the old definition of pathspec. Actually there was an earlier attempt that resulted in the pathspec matching tree traverser builtin-grep uses. Even though it has to work with trees (when grepping inside a tree-ish) and has optimizations not to open unnecessary subtrees similar to the one the diff-tree machinery has, it also knows how to handle globs. If we were to pick one of existing implementations for the longer term unification, I think that is probably the one we should build on top of.