Re: [PATCH 2/2] submodule.c: warn about missing submodule git directories

[Junio C Hamano <gitster@pobox.com>]

Stefan Beller <sbeller@google.com> writes:

> This is the continuation of f2d48994dc1 (submodule.c: submodule_move_head
> works with broken submodules, 2017-04-18), which tones down the case of
> "broken submodule" in case of a missing git directory of the submodule to
> be only a warning.

After seeing this warning, as we do not do any remedial action in
this codepath, the user with a repository in this state will keep
seeing the 'missing' message.  Wouldn't we want to give a hint in
addition (e.g. 'you can run "git submodule update $name" to
recover', or something like that)?

The MOVE_HEAD_FORCE codepath that follows this hunk is, eh, already
forcing to correct the situation, so there is no need to touch that,
which makes sense, if I understand correctly.

> Signed-off-by: Stefan Beller <sbeller@google.com>
> ---
>  submodule.c                   | 16 ++++++++++++++++
>  t/t2013-checkout-submodule.sh |  2 +-
>  2 files changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/submodule.c b/submodule.c
> index 50cbf5f13ed..689439a3d0c 100644
> --- a/submodule.c
> +++ b/submodule.c
> @@ -1641,6 +1641,22 @@ int submodule_move_head(const char *path,
>  		} else {
>  			char *gitdir = xstrfmt("%s/modules/%s",
>  				    get_git_common_dir(), sub->name);
> +
> +			if (!is_git_directory(gitdir)) {
> +				/*
> +				 * It is safe to assume we could just clone
> +				 * the submodule here, as we passed the
> +				 * is_submodule_active test above (i.e. the
> +				 * user is interested in this submodule.
> +				 *
> +				 * However as this code path is exercised
> +				 * for operations that typically do not involve
> +				 * network operations, let's not do that for now.
> +				 */
> +				warning(_("Submodule '%s' missing"), path);
> +				free(gitdir);
> +				return 0;
> +			}
>  			connect_work_tree_and_git_dir(path, gitdir, 0);
>  			free(gitdir);
>  
> diff --git a/t/t2013-checkout-submodule.sh b/t/t2013-checkout-submodule.sh
> index c69640fc341..82ef4576b91 100755
> --- a/t/t2013-checkout-submodule.sh
> +++ b/t/t2013-checkout-submodule.sh
> @@ -81,7 +81,7 @@ test_expect_success 'setup superproject with historic submodule' '
>  	test_must_be_empty super1/.gitmodules
>  '
>  
> -test_expect_failure 'checkout old state with deleted submodule' '
> +test_expect_success 'checkout old state with deleted submodule' '
>  	test_when_finished "rm -rf super1 sub1 super1_clone" &&
>  	git clone --recurse-submodules super1 super1_clone &&
>  	git -C super1_clone checkout --recurse-submodules historic_state