submodule: add absorb-git-dir function

diff --git a/t/t4053-diff-no-index.sh b/t/t4053-diff-no-index.sh
index 6eb83211b593ecea798eba3790b9c76fc7d3aa60..453e6c35eb89fd82649401cb20a462c560a102cf 100755 (executable)
--- a/t/t4053-diff-no-index.sh
+++ b/t/t4053-diff-no-index.sh
@@ -89,4 +89,42 @@ test_expect_success 'turning a file into a directory' '
        )
 '
 
+test_expect_success 'diff from repo subdir shows real paths (explicit)' '
+       echo "diff --git a/../../non/git/a b/../../non/git/b" >expect &&
+       test_expect_code 1 \
+               git -C repo/sub \
+               diff --no-index ../../non/git/a ../../non/git/b >actual &&
+       head -n 1 <actual >actual.head &&
+       test_cmp expect actual.head
+'
+
+test_expect_success 'diff from repo subdir shows real paths (implicit)' '
+       echo "diff --git a/../../non/git/a b/../../non/git/b" >expect &&
+       test_expect_code 1 \
+               git -C repo/sub \
+               diff ../../non/git/a ../../non/git/b >actual &&
+       head -n 1 <actual >actual.head &&
+       test_cmp expect actual.head
+'
+
+test_expect_success 'diff --no-index from repo subdir respects config (explicit)' '
+       echo "diff --git ../../non/git/a ../../non/git/b" >expect &&
+       test_config -C repo diff.noprefix true &&
+       test_expect_code 1 \
+               git -C repo/sub \
+               diff --no-index ../../non/git/a ../../non/git/b >actual &&
+       head -n 1 <actual >actual.head &&
+       test_cmp expect actual.head
+'
+
+test_expect_success 'diff --no-index from repo subdir respects config (implicit)' '
+       echo "diff --git ../../non/git/a ../../non/git/b" >expect &&
+       test_config -C repo diff.noprefix true &&
+       test_expect_code 1 \
+               git -C repo/sub \
+               diff ../../non/git/a ../../non/git/b >actual &&
+       head -n 1 <actual >actual.head &&
+       test_cmp expect actual.head
+'
+
 test_done