patchsubmodule: correct error message for missing commits.

> When a submodule diff should be displayed we currently just add the
> submodule objects to the main object store and then e.g. walk the
> revision graph and create a summary for that submodule.
>
> It is possible that we are missing the submodule either completely or
> partially, which we currently differentiate with different error messages
> depending on whether (1) the whole submodule object store is missing or
> (2) just the needed for this particular diff. (1) is reported as
> "not initialized", and (2) is reported as "commits not present".
>
> If a submodule is deinit'ed its repository data is still around inside
> the superproject, such that the diff can still be produced. In that way
> the error message (1) is misleading as we can have a diff despite the
> submodule being not initialized.
>
> Downgrade the error message (1) to be the same as (2) and just say
> the commits are not present, as that is the true reason why the diff
> cannot be shown.
>
> Signed-off-by: Stefan Beller <sbeller@google.com>

> ---
>  submodule.c                               | 2 +-
>  t/t4059-diff-submodule-not-initialized.sh | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/submodule.c b/submodule.c
> index 6531c5d609..280c246477 100644
> --- a/submodule.c
> +++ b/submodule.c
> @@ -567,7 +567,7 @@ static void show_submodule_header(FILE *f, const char *path,
>
>         if (add_submodule_odb(path)) {
>                 if (!message)
> -                       message = "(not initialized)";
> +                       message = "(commits not present)";
>                 goto output_header;
>         }
>
> diff --git a/t/t4059-diff-submodule-not-initialized.sh b/t/t4059-diff-submodule-not-initialized.sh
> index cd70fd5192..49bca7b48d 100755
> --- a/t/t4059-diff-submodule-not-initialized.sh
> +++ b/t/t4059-diff-submodule-not-initialized.sh
> @@ -95,7 +95,7 @@ test_expect_success 'submodule not initialized in new clone' '
>         git clone . sm3 &&
>         git -C sm3 diff-tree -p --no-commit-id --submodule=log HEAD >actual &&
>         cat >expected <<-EOF &&
> -       Submodule sm1 $smhead1...$smhead2 (not initialized)
> +       Submodule sm1 $smhead1...$smhead2 (commits not present)
>         EOF
>         test_cmp expected actual
>  '
> --
> 2.14.0.rc0.3.g6c2e499285
>

> When a submodule diff should be displayed we currently just add the
> submodule objects to the main object store and then e.g. walk the
> revision graph and create a summary for that submodule.
>
> It is possible that we are missing the submodule either completely or
> partially, which we currently differentiate with different error messages
> depending on whether (1) the whole submodule object store is missing or
> (2) just the needed for this particular diff. (1) is reported as
> "not initialized", and (2) is reported as "commits not present".
>
> If a submodule is deinit'ed its repository data is still around inside
> the superproject, such that the diff can still be produced. In that way
> the error message (1) is misleading as we can have a diff despite the
> submodule being not initialized.
>
> Downgrade the error message (1) to be the same as (2) and just say
> the commits are not present, as that is the true reason why the diff
> cannot be shown.
>
> Signed-off-by: Stefan Beller <sbeller@google.com>
> ---