From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6BA88C07E96 for ; Tue, 13 Jul 2021 07:52:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 553DB61288 for ; Tue, 13 Jul 2021 07:52:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234157AbhGMHzL (ORCPT ); Tue, 13 Jul 2021 03:55:11 -0400 Received: from cloud.peff.net ([104.130.231.41]:47562 "EHLO cloud.peff.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233762AbhGMHzL (ORCPT ); Tue, 13 Jul 2021 03:55:11 -0400 Received: (qmail 32343 invoked by uid 109); 13 Jul 2021 07:52:21 -0000 Received: from Unknown (HELO peff.net) (10.0.1.2) by cloud.peff.net (qpsmtpd/0.94) with ESMTP; Tue, 13 Jul 2021 07:52:21 +0000 Authentication-Results: cloud.peff.net; auth=none Received: (qmail 7388 invoked by uid 111); 13 Jul 2021 07:52:23 -0000 Received: from coredump.intra.peff.net (HELO sigill.intra.peff.net) (10.0.0.2) by peff.net (qpsmtpd/0.94) with (TLS_AES_256_GCM_SHA384 encrypted) ESMTPS; Tue, 13 Jul 2021 03:52:23 -0400 Authentication-Results: peff.net; auth=none Date: Tue, 13 Jul 2021 03:52:21 -0400 From: Jeff King To: Martin =?utf-8?B?w4VncmVu?= Cc: Junio C Hamano , git@vger.kernel.org, Taylor Blau Subject: Re: [PATCH v2] load_ref_decorations(): fix decoration with tags Message-ID: References: <20210713074018.232372-1-martin.agren@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210713074018.232372-1-martin.agren@gmail.com> Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org [+cc Junio; this patch looks good to me, and should go on top of jk/log-decorate-optim, which is in 'next' and has a pretty ugly regression] On Tue, Jul 13, 2021 at 09:40:18AM +0200, Martin Ågren wrote: > Commit 88473c8bae ("load_ref_decorations(): avoid parsing non-tag > objects", 2021-06-22) introduced a shortcut to `add_ref_decoration()`: > Rather than calling `parse_object()`, we go for `oid_object_info()` and > then `lookup_object_by_type()` using the type just discovered. As > detailed in the commit message, this provides a significant time saving. > > Unfortunately, it also changes the behavior: We lose all annotated tags > from the decoration. > > The reason this happens is in the loop where we try to peel the tags, we > won't necessarily have parsed that first object. If we haven't, its > `tag` will be NULL, so nothing will be displayed, and its `tagged` will > also be NULL, so we won't peel any further. Thanks, nicely explained. > Note how this commit could have been done as an optimization before > 88473c8bae: When our peeling hits a non-tag, we won't parse that tagged > object only to immediately end the loop. Yep, thanks for mentioning this, as it's somewhat subtle. > On Tue, 13 Jul 2021 at 02:06, Jeff King wrote: > > > > Your fix is _almost_ there. > > It's very kind of you to put it like that. I've picked up your > suggestions and have tried to summarize my understanding of the issue > and the fix in the commit message. When I wrote that, I thought the fix would just be: if (obj_type == OBJ_TAG) parse_object(...); which really would put it only one line off of your fix. :) > > That's the minimum needed to unbreak things. I think we could do even > > better, though. There is no need for us to parse a commit object pointed > > to by a tag here. We should only be parsing tags we see (whether at the > > top-level or recursively). > > Maybe you wrote this before circling back and actually writing that > "even better" thing? Because it seems to me like that's what you did. > Maybe I'm still missing something. Nope, I'm just dumb. I wrote what I sent in the other email (rather than just adding the "if" as above) because it only involved having a single parse_object() call in the function. To my credit, I did realize about an hour after sending the other email that I had in fact done the "better thing" quite accidentally. But I really like how you explained it in the commit message here, which I had not quite thought through. > log-tree.c | 4 ++-- > t/t4202-log.sh | 9 +++++++++ Patch looks good. Thanks for noticing the problem and cleaning up my mess. -Peff