From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael J Gruber Subject: Re: equal-tree-merges as way to make rebases fast-forward-able Date: Mon, 30 Nov 2009 16:35:57 +0100 Message-ID: <4B13E65D.3050504@drmicha.warpmail.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: git@vger.kernel.org To: "Bernhard R. Link" X-From: git-owner@vger.kernel.org Mon Nov 30 16:37:17 2009 Return-path: Envelope-to: gcvg-git-2@lo.gmane.org Received: from vger.kernel.org ([209.132.176.167]) by lo.gmane.org with esmtp (Exim 4.50) id 1NF8JQ-0004Qr-PC for gcvg-git-2@lo.gmane.org; Mon, 30 Nov 2009 16:37:17 +0100 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752713AbZK3PhG (ORCPT ); Mon, 30 Nov 2009 10:37:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752187AbZK3PhF (ORCPT ); Mon, 30 Nov 2009 10:37:05 -0500 Received: from out4.smtp.messagingengine.com ([66.111.4.28]:51842 "EHLO out4.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752466AbZK3PhE (ORCPT ); Mon, 30 Nov 2009 10:37:04 -0500 Received: from compute2.internal (compute2.internal [10.202.2.42]) by gateway1.messagingengine.com (Postfix) with ESMTP id 72787C5711; Mon, 30 Nov 2009 10:37:09 -0500 (EST) Received: from heartbeat2.messagingengine.com ([10.202.2.161]) by compute2.internal (MEProxy); Mon, 30 Nov 2009 10:37:09 -0500 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=messagingengine.com; h=message-id:date:from:mime-version:to:cc:subject:references:in-reply-to:content-type:content-transfer-encoding; s=smtpout; bh=oQC0KQA6DKpmB09vNx0DNBYVwD8=; b=SQHxN49+kFNmSK/5hzdVa1SYWo9pUKvGNVq3RhVjSvkzwW0pe+bEXmPKViCueB7pWOjb6NafDx3dpa1rcAL4x9J2plrYhUQOV3HaJjcEIA6FyhtRA+yXZiiz2xYLhMtF3zDMwkZAkBEXyYjilRh/BVexyX2/3Xcnm48qBCrScKE= X-Sasl-enc: h8s4nEA1rnnjuti92BY8XAqUWqf3YNgfpWqTEoN2ttDD 1259595429 Received: from localhost.localdomain (whitehead.math.tu-clausthal.de [139.174.44.12]) by mail.messagingengine.com (Postfix) with ESMTPSA id 9E8801A6A6; Mon, 30 Nov 2009 10:37:08 -0500 (EST) User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.6pre) Gecko/20091127 Lightning/1.0b1pre Shredder/3.0.1pre In-Reply-To: Sender: git-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Archived-At: Bernhard R. Link venit, vidit, dixit 30.11.2009 15:43: > The itch this idea is supposed to scratch is the problem that a rebase > or a amended commit is no longer a fast-forward, so cannot be easily > pulled. Do you mean pushed? For pull, the state of the branch on the receiving side play a role, of course. > While this is not a problem in most workflows, as one can either merge > or keep everything private and rebase until published, it would be nice > to have a way for cases in between, where both a clean presentable > commit order is to be maintained and people (or yourself from different > repositories) should be able to easily upgrade to newer versions without > an error-prone not-fast-forward. > > My idea to solve this is combining both histories, the rebased/revised > history and the actualy history, marking with some "equal-tree-merge" > the point where they have the same result. > The following mails show some patches to implement this by means of > a merge where all parents have the same tree and some special casing > when encountering such a thing. This has the advantage that older git > version will just see strange merges and may present both histories, > but otherwise just work. Without having the time to go through the detailed setup you described below (sorry), I'm wondering how this differs from what Git calls a trivial merge? Is it merely about asserting that you merge coinciding (heads with) trees? Michael