t: use test_might_fail for diff and grep

diff --git a/t/t4009-diff-rename-4.sh b/t/t4009-diff-rename-4.sh
index 57c094fdcea160a7816680d66efac9c05dd57cc8..3641fd84d68612786ab55beb780209c89311e105 100755 (executable)
--- a/t/t4009-diff-rename-4.sh
+++ b/t/t4009-diff-rename-4.sh
@@ -11,7 +11,7 @@ test_description='Same rename detection as t4003 but testing diff-raw -z.
 
 test_expect_success \
     'prepare reference tree' \
-    'cat "$TEST_DIRECTORY"/../COPYING >COPYING &&
+    'cat "$TEST_DIRECTORY"/diff-lib/COPYING >COPYING &&
      echo frotz >rezrov &&
     git update-index --add COPYING rezrov &&
     tree=$(git write-tree) &&
@@ -78,7 +78,7 @@ test_expect_success \
 
 test_expect_success \
     'prepare work tree once again' \
-    'cat "$TEST_DIRECTORY"/../COPYING >COPYING &&
+    'cat "$TEST_DIRECTORY"/diff-lib/COPYING >COPYING &&
      git update-index --add --remove COPYING COPYING.1'
 
 git diff-index -z -C --find-copies-harder $tree >current