Re: [PATCH] merge-recursive: Handle addition of submodule on our side of history

[Stefan Beller <sbeller@google.com>]

+cc Ефимов Василий <real@ispras.ru> who reported the issue at
https://public-inbox.org/git/743acc29-85bb-3773-b6a0-68d4a0b8fd63@ispras.ru/

On Tue, Nov 14, 2017 at 9:31 AM, Elijah Newren <newren@gmail.com> wrote:
> The code for a newly added path assumed that the path was a normal file,
> and thus checked for there being a directory still being in the way of
> the file.  Note that since unpack_trees() does path-in-the-way checks
> already, the only way for there to be a directory in the way at this
> point in the code, is if there is some kind of D/F conflict in the merge.
>
> For a submodule addition on HEAD's side of history, the submodule would
> have already been present.  This means that we do expect there to be a
> directory present but should not consider it to be "in the way"; instead,
> it's the expected submodule.  So, when there's a submodule addition from
> HEAD's side, don't bother checking the working copy for a directory in
> the way.
>
> Signed-off-by: Elijah Newren <newren@gmail.com>
> ---
> This commit is based on top of sb/test-cherry-pick-submodule-getting-in-a-way.

Thanks for getting the discussion started here (and fixing the bug),
based on your input in
https://public-inbox.org/git/CABPp-BHDrw_dAESic3xK7kC3jMgKeNQuPQF69OpbVYhRkbhJsw@mail.gmail.com/
I adapted the test case locally to have two tests one file/submodule
and a submodule/file conflict, after the setup which boroows a lot of
code from the
existing test, we'll have:

    test_expect_success 'unrelated submodule/file conflict is ignored' '
    (
        cd a_repo &&
       git checkout with_sub^0 &&
        git cherry-pick with_file^0
    )
    '

    test_expect_success 'unrelated file/submodule conflict is ignored' '
    (
        cd a_repo &&
        git checkout with_file^0 &&
        git cherry-pick with_sub^0
    )
    '

and the other case now fails. I'll take a look into that. I think we'd need to
check either a_mode or b_mode to be a submodule depending on which side
the submodule occured.

So I'll build on top of this patch to fix the other way, too.

>
>  merge-recursive.c                | 5 +++--
>  t/t3512-cherry-pick-submodule.sh | 2 +-
>  2 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/merge-recursive.c b/merge-recursive.c
> index 1d3f8f0d22..9fb0b9f8fd 100644
> --- a/merge-recursive.c
> +++ b/merge-recursive.c
> @@ -1901,8 +1901,9 @@ static int process_entry(struct merge_options *o,
>                         oid = b_oid;
>                         conf = _("directory/file");
>                 }
> -               if (dir_in_way(path, !o->call_depth,
> -                              S_ISGITLINK(a_mode))) {
> +               if (dir_in_way(path,
> +                              !o->call_depth && !S_ISGITLINK(a_mode),
> +                              0)) {

The last flag is_empty_ok is ok to keep at 0, I think.

Thanks,
Stefan