From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [PATCH 0/3] Teach Git about the patience diff algorithm Date: Wed, 7 Jan 2009 12:25:27 -0800 (PST) Message-ID: References: <20081104152351.GA21842@artemis.corp> <20081104004001.GB29458@artemis.corp> <20081104083042.GB3788@artemis.corp> <20081104152351.GA21842@artemis.corp> <20090106111712.GB30766@artemis.corp> <1231359317.6011.12.camel@maia.lan> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: Johannes Schindelin , Pierre Habouzit , davidel@xmailserver.org, Francis Galiegue , Git ML To: Sam Vilain X-From: git-owner@vger.kernel.org Wed Jan 07 21:27:11 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 1LKezb-0005rs-Os for gcvg-git-2@gmane.org; Wed, 07 Jan 2009 21:27:08 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760480AbZAGUZn (ORCPT ); Wed, 7 Jan 2009 15:25:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760344AbZAGUZm (ORCPT ); Wed, 7 Jan 2009 15:25:42 -0500 Received: from smtp1.linux-foundation.org ([140.211.169.13]:33544 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760184AbZAGUZl (ORCPT ); Wed, 7 Jan 2009 15:25:41 -0500 Received: from imap1.linux-foundation.org (imap1.linux-foundation.org [140.211.169.55]) by smtp1.linux-foundation.org (8.14.2/8.13.5/Debian-3ubuntu1.1) with ESMTP id n07KPRjH025250 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 7 Jan 2009 12:25:28 -0800 Received: from localhost (localhost [127.0.0.1]) by imap1.linux-foundation.org (8.13.5.20060308/8.13.5/Debian-3ubuntu1.1) with ESMTP id n07KPRap022707; Wed, 7 Jan 2009 12:25:27 -0800 X-X-Sender: torvalds@localhost.localdomain In-Reply-To: <1231359317.6011.12.camel@maia.lan> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) X-Spam-Status: No, hits=-3.947 required=5 tests=AWL,BAYES_00,OSDL_HEADER_SUBJECT_BRACKETED X-Spam-Checker-Version: SpamAssassin 3.2.4-osdl_revision__1.47__ X-MIMEDefang-Filter: lf$Revision: 1.188 $ X-Scanned-By: MIMEDefang 2.63 on 140.211.169.13 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: On Thu, 8 Jan 2009, Sam Vilain wrote: > > Whatever happens, the current deterministic diff algorithm needs to stay > for generating patch-id's... those really can't be allowed to change. Sure they can. We never cache patch-id's over a long time. And we _have_ changed xdiff to modify the output of the patches before, quite regardless of any patience issues: see commit 9b28d55401a529ff08c709f42f66e765c93b0a20, which admittedly doesn't affect any _normal_ diffs, but can generate subtly different results for some cases. It's true that we want the diff algorithm to be deterministic in the sense that over the run of a _single_ rebase operation, the diff between two files should give similar and deterministic results, but that's certainly true of patience diff too. Linus