From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-2.7 required=3.0 tests=AWL,BAYES_00, FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS, RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD shortcircuit=no autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by dcvr.yhbt.net (Postfix) with ESMTP id AB4322047F for ; Sat, 30 Sep 2017 15:12:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751505AbdI3PME (ORCPT ); Sat, 30 Sep 2017 11:12:04 -0400 Received: from mout.gmx.net ([212.227.15.18]:59627 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751048AbdI3PMB (ORCPT ); Sat, 30 Sep 2017 11:12:01 -0400 Received: from virtualbox ([37.201.193.73]) by mail.gmx.com (mrgmx003 [212.227.17.190]) with ESMTPSA (Nemesis) id 0LbdE3-1dUjIW0FQZ-00lCLk; Sat, 30 Sep 2017 17:11:55 +0200 Date: Sat, 30 Sep 2017 17:11:53 +0200 (CEST) From: Johannes Schindelin X-X-Sender: virtualbox@virtualbox To: Jeff Hostetler cc: Philip Oakley , Pavel Kretov , git@vger.kernel.org Subject: Re: [idea] File history tracking hints In-Reply-To: <5fb263a8-d83b-64a7-812f-fd8e3748feb6@jeffhostetler.com> Message-ID: References: <04DDB36236444FFD8C3668AA7B62B154@PhilipOakley> <5fb263a8-d83b-64a7-812f-fd8e3748feb6@jeffhostetler.com> User-Agent: Alpine 2.21.1 (DEB 209 2017-03-23) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Provags-ID: V03:K0:rq7D8zzskp4El4jr/9vewiHolin3HiQPhDtMkTHjNYOWpImZ8fa oGU/822VZ5u45pB93lUZ0+Kk0SE2Q14xpV8/U83zrBq9wv4S+BnPFNul0a2t3YMs2W6CNSS +HSQ+OeGvHR8hwRQihn2Hp1eVVRhGZbiyYGeboTu7gvUbmSGysZQ/jtsuG86FYEi4QNQ+X5 hBWqTYqixTl/Lt1KWziIw== X-UI-Out-Filterresults: notjunk:1;V01:K0:Kqlz+TRnodk=:Bx/DGSqGWEwJ5mLNZX01rE /scg4yqScjl1IJoEpzyLdSkftE+gEvCXM+Ifpi0lz7VrIVBOTnE9uYoCqFN19bl8VyuQzwP/a b49VFy8zlFyUUBUssFVcGqRu9A5Ti3GAedwLSP3lSbclVlPK88pF9YgAoadZGM6Mw9TIzjSED /SvOlz92x6SD1ToWKS4eoNwcVt5JRqCkepV+kLWPOuwUH+B19RABy0XIxnrO60wFIhONkoxwz daAz7AvPqQ/g/JNY7FgMVtb8ChhKCNzlK6OlwX976SrWE28MaA5nca6ZvBEeeG9ZrcjrBj1Qa IHcSI74El3OqJwezzgS27lwdPkcvdraMhz6RTRpSDEpeemplqoRdwBapJ5lsOgu9SY+Fg68VU pqbHfqlBSjjEjPwHZNi99Se+YtrwBf0ReDVxZHMZ9YdZOF2heFIVP9aA1Ht8gUpPzYDhcj5Pj dYuU8K8aM+zUBdOdVm0tYWiARdckNviOdpL4RDGWws7c07n21seOnHH17tYRQiRPsugfdK5YA IFALs/FCga8hIaq1jfB/JI6G2/rwGxUwZwtk3vezQ8jY3EehqQuJyCYrqQnq4516yxxBRM5Ih Ae6z3p9tq6OZ1dCJVjlNmRUsEfaJzCZQbNaycLQUoWTh/cxfiQh8yyxdJdbygT8xwaNA8Clxx 6gmQtyNRplcw2VE8615vT872BMW3kL+//WEGQuaizmPGJYKxNc8aBPR19G/q4IRl8EmNm/fWE hNBFMTryKnJXHDqNyWzk/KWRaJ6kt9V9FCPjz12Y6OpJFsYHARm+4nxXqyid2m8xh68rSxHM/ 0omOB+VokUyuWGpglSmfoVsuFOrOmiQHOpJmHiqdBEZ3gdyonc= Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Hi Jeff, On Sat, 30 Sep 2017, Jeff Hostetler wrote: > On 9/29/2017 7:12 PM, Johannes Schindelin wrote: > > > Therefore, it would be good to have a way to tell Git about renames > > explicitly so that it does not even need to use its heuristics. > > Agreed. > > It would be nice if every file (and tree) had a permanent GUID > associated with it. Then the filename/pathname becomes a property > of the GUIDs. Then you can exactly know about moves/renames with > minimal effort (and no guessing). But I suppose that ship has sailed... Yes, that ship has sailed. But we still could teach Git to understand certain "hints" (that would be really more like "cluebats"). So while we cannot have any GUIDs that are persistent across renames/moves (and which users would probably get wrong all the time by using third-party tools that are not Git-rename aware), we have unique identifiers: the object names. And we could easily have a lookup table of pairs of object names, telling Git that they were source and target of a rename. When Git would try to figure out whether anything was renamed, it would first look at that lookup table and save itself a lot of work (and opportunity to fail) and short-cut the rename detection. Ciao, Johannes