Re: [PATCH v4] submodule merge: update conflict error message

>
> Hi Calvin,
>
> On Tue, 12 Jul 2022, Calvin Wan wrote:
>
> > diff --git a/t/t6437-submodule-merge.sh b/t/t6437-submodule-merge.sh
> > index 178413c22f..cc1a312661 100755
> > --- a/t/t6437-submodule-merge.sh
> > +++ b/t/t6437-submodule-merge.sh
> > @@ -103,8 +103,25 @@ test_expect_success 'setup for merge search' '
> >        echo "file-c" > file-c &&
> >        git add file-c &&
> >        git commit -m "sub-c") &&
> > -     git commit -a -m "c" &&
> > +     git commit -a -m "c")
> > +'
> > +
> > +test_expect_success 'merging should conflict for non fast-forward' '
> > +     (cd merge-search &&
> > +      git checkout -b test-nonforward-a b &&
> > +       if test "$GIT_TEST_MERGE_ALGORITHM" = ort
> > +       then
> > +             test_must_fail git merge c >actual
> > +       else
> > +             test_must_fail git merge c 2> actual
> > +       fi &&
> > +      sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
> > +      grep "$sub_expect" actual &&
>
> No matter how hard I tried to stare at the code, no matter whether I
> looked at `cw/submodule-merge-messages` or `seen`, I cannot see how this
> `grep` could ever succeed when `GIT_TEST_MERGE_ALGORITHM=recursive`: only
> the `ort` code has been taught this new trick.

> In fact, when I run this locally with
> `GIT_TEST_MERGE_ALGORITHM=recursive`, it not only fails (as shown here:
> https://github.com/gitgitgadget/git/runs/7349612861?check_suite_focus=true#step:4:1833
> and here:
> https://github.com/gitgitgadget/git/runs/7326925485?check_suite_focus=true#step:4:1820),
> it also leaves no error message in `actual`.
>
> So you probably want to move the `sub_expect` assignment and the `grep`
> into the `ort` clause of the conditional above.
>
> With this fixup, things seem to work over here:
>
> -- snip --
> diff --git a/t/t6437-submodule-merge.sh b/t/t6437-submodule-merge.sh
> index cc1a3126619..3892d0bf742 100755
> --- a/t/t6437-submodule-merge.sh
> +++ b/t/t6437-submodule-merge.sh
> @@ -111,12 +111,12 @@ test_expect_success 'merging should conflict for non fast-forward' '
>          git checkout -b test-nonforward-a b &&
>           if test "$GIT_TEST_MERGE_ALGORITHM" = ort
>           then
> -               test_must_fail git merge c >actual
> +               test_must_fail git merge c >actual &&
> +               sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
> +               grep "$sub_expect" actual
>           else
>                 test_must_fail git merge c 2> actual
>           fi &&
> -        sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
> -        grep "$sub_expect" actual &&
>          git reset --hard)
>  '
>
> @@ -153,13 +153,13 @@ test_expect_success 'merging should conflict for non fast-forward (resolution ex
>           git rev-parse sub-d > ../expect) &&
>           if test "$GIT_TEST_MERGE_ALGORITHM" = ort
>           then
> -               test_must_fail git merge c >actual
> +               test_must_fail git merge c >actual &&
> +               sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
> +               grep "$sub_expect" actual
>           else
>                 test_must_fail git merge c 2> actual
>           fi &&
>          grep $(cat expect) actual > /dev/null &&
> -        sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
> -        grep "$sub_expect" actual &&
>          git reset --hard)
>  '
>
> @@ -180,14 +180,14 @@ test_expect_success 'merging should fail for ambiguous common parent' '
>          ) &&
>          if test "$GIT_TEST_MERGE_ALGORITHM" = ort
>          then
> -               test_must_fail git merge c >actual
> +               test_must_fail git merge c >actual &&
> +               sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
> +               grep "$sub_expect" actual
>          else
>                 test_must_fail git merge c 2> actual
>          fi &&
>         grep $(cat expect1) actual > /dev/null &&
>         grep $(cat expect2) actual > /dev/null &&
> -       sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-c)" &&
> -       grep "$sub_expect" actual &&
>         git reset --hard)
>  '
>
> @@ -227,8 +227,11 @@ test_expect_success 'merging should fail for changes that are backwards' '
>
>         git checkout -b test-backward e &&
>         test_must_fail git merge f >actual &&
> -       sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-d)" &&
> -       grep "$sub_expect" actual)
> +       if test "$GIT_TEST_MERGE_ALGORITHM" = ort
> +       then
> +               sub_expect="go to submodule (sub), and either merge commit $(git -C sub rev-parse --short sub-d)" &&
> +               grep "$sub_expect" actual
> +       fi)
>  '
>
> -- snap --