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Subject: Re: [RFC/PATCH] refs: tone down the dwimmery in refname_match() for
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From:   Paolo Bonzini <pbonzini@redhat.com>
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Date:   Mon, 27 May 2019 14:33:10 +0200
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On 27/05/19 00:54, Ævar Arnfjörð Bjarmason wrote:
> This resulted in a case[1] where someone on LKML did:
> 
>     git push kvm +HEAD:tags/for-linus
> 
> Which would have created a new "tags/for-linus" branch in their "kvm"
> repository, except because they happened to have an existing
> "refs/tags/for-linus" reference we pushed there instead, and replaced
> an annotated tag with a lightweight tag.

Actually, I would not be surprised even if "git push foo
someref:tags/foo" _always_ created a lightweight tag (i.e. push to
refs/tags/foo).

In my opinion, the bug is that "git request-pull" should warn if the tag
is lightweight remotely but not locally, and possibly even vice versa.
Here is a simple testcase:

  # setup "local" repo
  mkdir -p testdir/a
  cd testdir/a
  git init
  echo a > test
  git add test
  git commit -minitial

  # setup "remote" repo
  git clone --bare . ../b

  # setup "local" tag
  echo b >> test
  git commit -msecond test
  git tag -mtag tag1

  # create remote lightweight tag and prepare a pull request
  git push ../b HEAD:refs/tags/tag1
  git request-pull HEAD^ ../b tags/tag1

Paolo