tests: grep portability fixes

diff --git a/t/t4027-diff-submodule.sh b/t/t4027-diff-submodule.sh
index 1fd3fb74d763026d4e20a38fe9d2ed48dda74fed..1c2edebb09bd6e1d7581365011c8500da57942c5 100755 (executable)
--- a/t/t4027-diff-submodule.sh
+++ b/t/t4027-diff-submodule.sh
@@ -3,7 +3,7 @@
 test_description='difference in submodules'
 
 . ./test-lib.sh
-. ../diff-lib.sh
+. "$TEST_DIRECTORY"/diff-lib.sh
 
 _z40=0000000000000000000000000000000000000000
 test_expect_success setup '
@@ -50,4 +50,11 @@ test_expect_success 'git diff-files --raw' '
        test_cmp expect actual.files
 '
 
+test_expect_success 'git diff (empty submodule dir)' '
+       : >empty &&
+       rm -rf sub/* sub/.git &&
+       git diff > actual.empty &&
+       test_cmp empty actual.empty
+'
+
 test_done