Re: Fetching tags overwrites existing tags

[Wink Saville <wink@saville.com>]

On Tue, Apr 24, 2018 at 5:52 PM, Junio C Hamano <gitster@pobox.com> wrote:
> Wink Saville <wink@saville.com> writes:
>
>> Ideally I would have liked the tags fetched from gbenchmark to have a prefix
>> of gbenchmark/, like the branches have, maybe something like:
>>
>> $ git fetch --tags gbenchmark
>> ...
>>  * [new branch]      v2              -> gbenchmark/v2
>>  * [new tag]         v0.0.9          -> gbenchmark/v0.0.9
>>  * [new tag]         v0.1.0          -> gbenchmark/v0.1.0
>>  * [new tag]         v1.0.0          -> gbenchmark/v1.0.0
>>  * [new tag]         v1.1.0          -> gbenchmark/v1.1.0
>>  * [new tag]         v1.2.0          -> gbenchmark/v1.2.0
>>  * [new tag]         v1.3.0          -> gbenchmark/v1.3.0
>>  * [new tag]         v1.4.0          -> gbenchmark/v1.4.0
>
> The tag namespace (refs/tags/) is considered a shared resource (I am
> not saying that that is the only valid world model---I am merely
> explaining why things are like they are), hence the auto-following
> tags will bring them to refs/tags/ (and I do not think there is no
> way to configure auto-following to place them elsewhere).
>
> But you could configure things yourself.
>
>     $ git init victim && cd victim
>     $ git remote add origin ../git.git
>     $ git config --add remote.origin.fetch \
>       "+refs/tags/*:refs/remote-tags/origin/*"
>     $ tail -n 4 .git/config
>     [remote "origin"]
>         url = ../git.git/
>         fetch = +refs/heads/*:refs/remotes/origin/*
>         fetch = +refs/tags/*:refs/remote-tags/origin/*
>     $ git fetch --no-tags
>
> The "--no-tags" option serves to decline the auto-following tags to
> refs/tags/ hierarchy; once your repository is configured this way,
> your initial and subsequent "git fetch" will copy refs it finds in
> refs/tags/ hierarchy over there to your refs/remote-tags/origin/
> hierarchy locally.

Interesting that kinda works, what about teaching git-remote to
understand a "--prefix-tags" option which would create the
"fetch = refs/tags/*:refs/remote-tags/origin" entry. And teach
git-fetch to use that entry if it exists and not require the "--no-tags"?

Of course I'm sure there are "lots" of other things to change, doing
a search for "remotes/" gives the following:

$ find . -type f -name '*.c' | xargs grep '\bremotes/' | sort -uk1,1
./builtin/branch.c: fmt = "refs/remotes/%s";
./builtin/checkout.c: skip_prefix(argv0, "remotes/", &argv0);
./builtin/clone.c: strbuf_addf(&branch_top, "refs/remotes/%s/", option_origin);
./builtin/describe.c:     !skip_prefix(path, "refs/remotes/", &path_to_match)) {
./builtin/fast-export.c: "refs/remotes/",
./builtin/fetch.c: else if (starts_with(rm->name, "refs/remotes/")) {
./builtin/merge.c: if (starts_with(found_ref, "refs/remotes/")) {
./builtin/pull.c: * refs/heads/<branch_name> to
refs/remotes/<remote_name>/<branch_name>.
./builtin/remote.c: strbuf_addf(tmp, "refs/heads/%s:refs/remotes/%s/%s",
./builtin/rev-parse.c: handle_ref_opt(arg, "refs/remotes/");
./builtin/show-branch.c: if (!starts_with(refname, "refs/remotes/"))
./contrib/examples/builtin-fetch--tool.c: else if
(!strncmp(remote_name, "refs/remotes/", 13)) {
./help.c: if (skip_prefix(refname, "refs/remotes/", &remote) &&
./log-tree.c: else if (starts_with(refname, "refs/remotes/"))
./ref-filter.c:        skip_prefix(refname, "refs/remotes/", &refname) ||
./refs.c: return refs_for_each_ref_in(refs, "refs/remotes/", fn, cb_data);
./remote.c: FILE *f = fopen_or_warn(git_path("remotes/%s", remote->name), "r");
./revision.c: for_each_glob_ref_in(handle_one_ref, optarg,
"refs/remotes/", &cb);
./sha1_name.c:     starts_with(refname, "refs/remotes/"))
./wt-status.c: skip_prefix(from, "refs/remotes/", &from);

-- wink