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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3A09C433FE for ; Sat, 8 Oct 2022 12:28:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229789AbiJHM22 (ORCPT ); Sat, 8 Oct 2022 08:28:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44428 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229502AbiJHM21 (ORCPT ); Sat, 8 Oct 2022 08:28:27 -0400 Received: from smtp.hosts.co.uk (smtp.hosts.co.uk [85.233.160.19]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 388754D15B for ; Sat, 8 Oct 2022 05:28:25 -0700 (PDT) Received: from 88-110-102-84.dynamic.dsl.as9105.com ([88.110.102.84] helo=[192.168.1.57]) by smtp.hosts.co.uk with esmtpa (Exim) (envelope-from ) id 1oh8wH-0006Z6-8J; Sat, 08 Oct 2022 13:28:22 +0100 Message-ID: <86355292-cb54-32c8-abf5-542fb4cf9ade@iee.email> Date: Sat, 8 Oct 2022 13:28:21 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.1 Subject: Re: [PATCH v2] symbolic-ref: teach "--[no-]recurse" option Content-Language: en-GB To: Junio C Hamano , git@vger.kernel.org Cc: Eric Sunshine References: From: Philip Oakley In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: git@vger.kernel.org Hi Junio On 08/10/2022 05:34, Junio C Hamano wrote: > Suppose you are managing many maintenance tracks in your project, > and some of the more recent ones are maint-2.36 and maint-2.37. > Further imagine that your project recently tagged the official 2.38 > release, which means you would need to start maint-2.38 track soon, > by doing: > > $ git checkout -b maint-2.38 v2.38.0^0 > $ git branch --list 'maint-2.3[6-9]' > * maint-2.38 > maint-2.36 > maint-2.37 > > So far, so good. But it also is reasonable to want not to have to > worry about which maintenance track is the latest, by pointing a > more generic-sounding 'maint' branch at it, by doing: > > $ git symbolic-ref refs/heads/maint refs/heads/maint-2.38 > > which would allow you to say "whichever it is, check out the latest > maintenance track", by doing: > > $ git checkout maint > $ git branch --show-current > maint-2.38 > > It is arguably better to say that we are on 'maint-2.38' rather than > on 'maint', and "git merge/pull" would record "into maint-2.38" and > not "into maint", so I think what we have is a good behaviour. > > One thing that is slightly irritating, however, is that I do not > think there is a good way (other than "cat .git/HEAD") to learn that > you checked out 'maint' to get into that state. Just like the output > of "git branch --show-current" shows above, "git symbolic-ref HEAD" > would report 'refs/heads/maint-2.38', bypassing the intermediate > symbolic ref at 'refs/heads/maint' that is pointed at by HEAD. > > The internal resolve_ref() API already has the necessary support for > stopping after resolving a single level of a symbolic-ref, and we > can expose it by adding a "--[no-]recurse" option to the command. > > Signed-off-by: Junio C Hamano > --- > > * Updates documentation, which was entirely lacking in v1, with no > other changes. > > Documentation/git-symbolic-ref.txt | 9 +++++++++ Is there also a need to update SubmittingPatches to clarify the distinctions between the generic name 'maint', the specific `maint-xx` branches, and the symbolic ref linkages from `maint`. The existence of the `maint-xx` branches, and where they came from, was something that eluded me for a long time. The descriptions give the impression there is just a single main branch, with a singular name, and that was the end of it. It was only much later when some security patches were pushed down to numerous older `maint-xx` branches. The use of the singular `maint` is also used in examples a number of places further cementing the singular maintenance view. A few words clarifying the `maint` vs `maint-x.yy` branches could help users past the confusion. -- Philip > builtin/symbolic-ref.c | 16 ++++++++++------ > t/t1401-symbolic-ref.sh | 14 ++++++++++++++ > 3 files changed, 33 insertions(+), 6 deletions(-) > > diff --git a/Documentation/git-symbolic-ref.txt b/Documentation/git-symbolic-ref.txt > index ef68ad2b71..3b5a97ea2b 100644 > --- a/Documentation/git-symbolic-ref.txt > +++ b/Documentation/git-symbolic-ref.txt > @@ -46,6 +46,15 @@ OPTIONS > When showing the value of as a symbolic ref, try to shorten the > value, e.g. from `refs/heads/master` to `master`. > > +--recurse:: > +--no-recurse:: > + When showing the value of as a symbolic ref, if > + refers to another symbolic ref, follow such a chain > + of symbolic refs until the result no longer points at a > + symbolic ref (`--recurse`, which is the default). > + `--no-recurse` stops after dereferencing only a single level > + of symbolic ref. > + > -m:: > Update the reflog for with . This is valid only > when creating or updating a symbolic ref. > diff --git a/builtin/symbolic-ref.c b/builtin/symbolic-ref.c > index e547a08d6c..1af27b3a68 100644 > --- a/builtin/symbolic-ref.c > +++ b/builtin/symbolic-ref.c > @@ -10,10 +10,13 @@ static const char * const git_symbolic_ref_usage[] = { > NULL > }; > > -static int check_symref(const char *HEAD, int quiet, int shorten, int print) > +static int check_symref(const char *HEAD, int quiet, int shorten, int recurse, int print) > { > - int flag; > - const char *refname = resolve_ref_unsafe(HEAD, 0, NULL, &flag); > + int resolve_flags, flag; > + const char *refname; > + > + resolve_flags = (recurse ? 0 : RESOLVE_REF_NO_RECURSE); > + refname = resolve_ref_unsafe(HEAD, resolve_flags, NULL, &flag); > > if (!refname) > die("No such ref: %s", HEAD); > @@ -35,13 +38,14 @@ static int check_symref(const char *HEAD, int quiet, int shorten, int print) > > int cmd_symbolic_ref(int argc, const char **argv, const char *prefix) > { > - int quiet = 0, delete = 0, shorten = 0, ret = 0; > + int quiet = 0, delete = 0, shorten = 0, recurse = 1, ret = 0; > const char *msg = NULL; > struct option options[] = { > OPT__QUIET(&quiet, > N_("suppress error message for non-symbolic (detached) refs")), > OPT_BOOL('d', "delete", &delete, N_("delete symbolic ref")), > OPT_BOOL(0, "short", &shorten, N_("shorten ref output")), > + OPT_BOOL(0, "recurse", &recurse, N_("recursively dereference (default)")), > OPT_STRING('m', NULL, &msg, N_("reason"), N_("reason of the update")), > OPT_END(), > }; > @@ -55,7 +59,7 @@ int cmd_symbolic_ref(int argc, const char **argv, const char *prefix) > if (delete) { > if (argc != 1) > usage_with_options(git_symbolic_ref_usage, options); > - ret = check_symref(argv[0], 1, 0, 0); > + ret = check_symref(argv[0], 1, 0, 0, 0); > if (ret) > die("Cannot delete %s, not a symbolic ref", argv[0]); > if (!strcmp(argv[0], "HEAD")) > @@ -65,7 +69,7 @@ int cmd_symbolic_ref(int argc, const char **argv, const char *prefix) > > switch (argc) { > case 1: > - ret = check_symref(argv[0], quiet, shorten, 1); > + ret = check_symref(argv[0], quiet, shorten, recurse, 1); > break; > case 2: > if (!strcmp(argv[0], "HEAD") && > diff --git a/t/t1401-symbolic-ref.sh b/t/t1401-symbolic-ref.sh > index 132a1b885a..773a6e8e01 100755 > --- a/t/t1401-symbolic-ref.sh > +++ b/t/t1401-symbolic-ref.sh > @@ -163,4 +163,18 @@ test_expect_success 'symbolic-ref can resolve d/f name (ENOTDIR)' ' > test_cmp expect actual > ' > > +test_expect_success 'symbolic-ref pointing at another' ' > + git update-ref refs/heads/maint-2.37 HEAD && > + git symbolic-ref refs/heads/maint refs/heads/maint-2.37 && > + git checkout maint && > + > + git symbolic-ref HEAD >actual && > + echo refs/heads/maint-2.37 >expect && > + test_cmp expect actual && > + > + git symbolic-ref --no-recurse HEAD >actual && > + echo refs/heads/maint >expect && > + test_cmp expect actual > +' > + > test_done