From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: [PATCH 2/3] patch-id: document new behaviour Date: Thu, 27 Mar 2014 11:25:14 +0200 Message-ID: <1395912239-29663-2-git-send-email-mst@redhat.com> References: <1395912239-29663-1-git-send-email-mst@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: jrnieder@gmail.com, peff@peff.net, gitster@pobox.com To: git@vger.kernel.org X-From: git-owner@vger.kernel.org Thu Mar 27 10:25:45 2014 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 1WT6ZD-00023e-BP for gcvg-git-2@plane.gmane.org; Thu, 27 Mar 2014 10:25:43 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753931AbaC0JZB (ORCPT ); Thu, 27 Mar 2014 05:25:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35673 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752043AbaC0JZA (ORCPT ); Thu, 27 Mar 2014 05:25:00 -0400 Received: from int-mx13.intmail.prod.int.phx2.redhat.com (int-mx13.intmail.prod.int.phx2.redhat.com [10.5.11.26]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s2R9Ov0F025865 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 27 Mar 2014 05:24:57 -0400 Received: from redhat.com (vpn1-6-224.ams2.redhat.com [10.36.6.224]) by int-mx13.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with SMTP id s2R9Ottb001377; Thu, 27 Mar 2014 05:24:55 -0400 Content-Disposition: inline In-Reply-To: <1395912239-29663-1-git-send-email-mst@redhat.com> X-Mutt-Fcc: =sent X-Scanned-By: MIMEDefang 2.68 on 10.5.11.26 Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Clarify that patch ID is now a sum of hashes, not a hash. Document --stable and --unstable flags. Signed-off-by: Michael S. Tsirkin --- Documentation/git-patch-id.txt | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) diff --git a/Documentation/git-patch-id.txt b/Documentation/git-patch-id.txt index 312c3b1..1bc6d52 100644 --- a/Documentation/git-patch-id.txt +++ b/Documentation/git-patch-id.txt @@ -8,14 +8,14 @@ git-patch-id - Compute unique ID for a patch SYNOPSIS -------- [verse] -'git patch-id' < +'git patch-id' [--stable | --unstable] < DESCRIPTION ----------- -A "patch ID" is nothing but a SHA-1 of the diff associated with a patch, with -whitespace and line numbers ignored. As such, it's "reasonably stable", but at -the same time also reasonably unique, i.e., two patches that have the same "patch -ID" are almost guaranteed to be the same thing. +A "patch ID" is nothing but a sum of SHA-1 of the diff hunks associated with a +patch, with whitespace and line numbers ignored. As such, it's "reasonably +stable", but at the same time also reasonably unique, i.e., two patches that +have the same "patch ID" are almost guaranteed to be the same thing. IOW, you can use this thing to look for likely duplicate commits. @@ -27,6 +27,17 @@ This can be used to make a mapping from patch ID to commit ID. OPTIONS ------- + +--stable:: + Use a symmetrical sum of hashes, such that order of + hunks in the diff does not affect the ID. + This is the default. + +--unstable:: + Use a non-symmetrical sum of hashes, such that order of + hunks in the diff affects the ID. + This was the default value for git 1.9 and older. + :: The diff to create the ID of. -- MST