rerere: teach rerere to handle nested conflicts

diff --git a/t/t4060-diff-submodule-option-diff-format.sh b/t/t4060-diff-submodule-option-diff-format.sh
index 33b661140d18083c7c721afc702c5b45beb584d1..4b168d0ed7ff2bbb1d93895de7fdf3f14bfe334e 100755 (executable)
--- a/t/t4060-diff-submodule-option-diff-format.sh
+++ b/t/t4060-diff-submodule-option-diff-format.sh
@@ -643,9 +643,11 @@ test_expect_success 'deleted submodule' '
        test_cmp expected actual
 '
 
-test_create_repo sm2 &&
-head7=$(add_file sm2 foo8 foo9) &&
-git add sm2
+test_expect_success 'create second submodule' '
+       test_create_repo sm2 &&
+       head7=$(add_file sm2 foo8 foo9) &&
+       git add sm2
+'
 
 test_expect_success 'multiple submodules' '
        git diff-index -p --submodule=diff HEAD >actual &&
@@ -746,6 +748,35 @@ test_expect_success 'diff --submodule=diff with .git file' '
        test_cmp expected actual
 '
 
+test_expect_success 'setup nested submodule' '
+       git submodule add -f ./sm2 &&
+       git commit -a -m "add sm2" &&
+       git -C sm2 submodule add ../sm2 nested &&
+       git -C sm2 commit -a -m "nested sub"
+'
+
+test_expect_success 'move nested submodule HEAD' '
+       echo "nested content" >sm2/nested/file &&
+       git -C sm2/nested add file &&
+       git -C sm2/nested commit --allow-empty -m "new HEAD"
+'
+
+test_expect_success 'diff --submodule=diff with moved nested submodule HEAD' '
+       cat >expected <<-EOF &&
+       Submodule nested a5a65c9..b55928c:
+       diff --git a/nested/file b/nested/file
+       new file mode 100644
+       index 0000000..ca281f5
+       --- /dev/null
+       +++ b/nested/file
+       @@ -0,0 +1 @@
+       +nested content
+       EOF
+       git -C sm2 diff --submodule=diff >actual 2>err &&
+       test_must_be_empty err &&
+       test_cmp expected actual
+'
+
 test_expect_success 'diff --submodule=diff recurses into nested submodules' '
        cat >expected <<-EOF &&
        Submodule sm2 contains modified content