correct usage help string for git-hash-object

diff --git a/t/t4027-diff-submodule.sh b/t/t4027-diff-submodule.sh
index 3d2d0816a3656a0df347fbd29571f5c38513c27f..ba6679c6e4032bb12e4206226f95770946ece8cc 100755 (executable)
--- a/t/t4027-diff-submodule.sh
+++ b/t/t4027-diff-submodule.sh
@@ -37,17 +37,24 @@ test_expect_success setup '
 
 test_expect_success 'git diff --raw HEAD' '
        git diff --raw --abbrev=40 HEAD >actual &&
-       diff -u expect actual
+       test_cmp expect actual
 '
 
 test_expect_success 'git diff-index --raw HEAD' '
        git diff-index --raw HEAD >actual.index &&
-       diff -u expect actual.index
+       test_cmp expect actual.index
 '
 
 test_expect_success 'git diff-files --raw' '
        git diff-files --raw >actual.files &&
-       diff -u expect actual.files
+       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