Subject: Re: [PATCH v2] remote-hg: do not fail on invalid bookmarks

From: Junio C Hamano <[email-masked]>
Date: Wed, 19 Mar 2014 14:51:37 -0700

Max Horn <[email-masked]> writes:

> Mercurial can have bookmarks pointing to "nullid" (the empty root
> revision), while Git can not have references to it.
> When cloning or fetching from a Mercurial repository that has such a
> bookmark, the import will fail because git-remote-hg will not be able to
> create the corresponding reference.
>
> Warn the user about the invalid reference, and continue the import,
> instead of stopping right away.

The text above is identical to what Antoine wrote in e8d48743
(remote-hg: do not fail on invalid bookmarks, 2013-12-29); I'd
assume that this is to replace it.

But the code seems to do more, and I think that is related to the
detailed analysis you dug up from the archive earlier and then
summarised in your $gmane/244440.  Can you say a bit more about
these fake-bmark and bmark checking like you did in that original
3-patch series?

Thanks.

> Also add some test cases for this issue.
>
> Reported-by: Antoine Pelisse <[email-masked]>
> Signed-off-by: Max Horn <[email-masked]>
> ---
>  contrib/remote-helpers/git-remote-hg |  6 +++++
>  contrib/remote-helpers/test-hg.sh    | 48 ++++++++++++++++++++++++++++++++++++
>  2 files changed, 54 insertions(+)
>
> diff --git a/contrib/remote-helpers/git-remote-hg b/contrib/remote-helpers/git-remote-hg
> index eb89ef6..49b2c2e 100755
> --- a/contrib/remote-helpers/git-remote-hg
> +++ b/contrib/remote-helpers/git-remote-hg
> @@ -625,6 +625,12 @@ def list_head(repo, cur):
>  def do_list(parser):
>      repo = parser.repo
>      for bmark, node in bookmarks.listbookmarks(repo).iteritems():
> +        if node == '0000000000000000000000000000000000000000':
> +            if fake_bmark == 'default' and bmark == 'master':
> +                pass
> +            else:
> +                warn("Ignoring invalid bookmark '%s'", bmark)
> +                continue
>          bmarks[bmark] = repo[node]
>  
>      cur = repo.dirstate.branch()
> diff --git a/contrib/remote-helpers/test-hg.sh b/contrib/remote-helpers/test-hg.sh
> index a933b1e..8d01b32 100755
> --- a/contrib/remote-helpers/test-hg.sh
> +++ b/contrib/remote-helpers/test-hg.sh
> @@ -772,4 +772,52 @@ test_expect_success 'remote double failed push' '
>  	)
>  '
>  
> +test_expect_success 'clone remote with master null bookmark' '
> +	test_when_finished "rm -rf gitrepo* hgrepo*" &&
> +
> +	(
> +	hg init hgrepo &&
> +	cd hgrepo &&
> +	echo a >a &&
> +	hg add a &&
> +	hg commit -m a &&
> +	hg bookmark -r null master
> +	) &&
> +
> +	git clone "hg::hgrepo" gitrepo &&
> +	check gitrepo HEAD a
> +'
> +
> +test_expect_success 'clone remote with default null bookmark' '
> +	test_when_finished "rm -rf gitrepo* hgrepo*" &&
> +
> +	(
> +	hg init hgrepo &&
> +	cd hgrepo &&
> +	echo a >a &&
> +	hg add a &&
> +	hg commit -m a &&
> +	hg bookmark -r null -f default
> +	) &&
> +
> +	git clone "hg::hgrepo" gitrepo &&
> +	check gitrepo HEAD a
> +'
> +
> +test_expect_success 'clone remote with generic null bookmark' '
> +	test_when_finished "rm -rf gitrepo* hgrepo*" &&
> +
> +	(
> +	hg init hgrepo &&
> +	cd hgrepo &&
> +	echo a >a &&
> +	hg add a &&
> +	hg commit -m a &&
> +	hg bookmark -r null bmark
> +	) &&
> +
> +	git clone "hg::hgrepo" gitrepo &&
> +	check gitrepo HEAD a
> +'
> +
>  test_done