read-cache.c: fix writing "link" index ext with null base oid

diff --git a/t/t3310-notes-merge-manual-resolve.sh b/t/t3310-notes-merge-manual-resolve.sh
index 68436eed82101cdfcc7f93fea0681083b546cf2a..2dea846e259dbb8cd163b82f6e551c9823cbd180 100755 (executable)
--- a/t/t3310-notes-merge-manual-resolve.sh
+++ b/t/t3310-notes-merge-manual-resolve.sh
@@ -337,7 +337,7 @@ EOF
        git notes merge --commit &&
        # No .git/NOTES_MERGE_* files left
        test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
-       test_cmp /dev/null output &&
+       test_must_be_empty output &&
        # Merge commit has pre-merge y and pre-merge z as parents
        test "$(git rev-parse refs/notes/m^1)" = "$(cat pre_merge_y)" &&
        test "$(git rev-parse refs/notes/m^2)" = "$(cat pre_merge_z)" &&
@@ -399,7 +399,7 @@ test_expect_success 'abort notes merge' '
        git notes merge --abort &&
        # No .git/NOTES_MERGE_* files left
        test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
-       test_cmp /dev/null output &&
+       test_must_be_empty output &&
        # m has not moved (still == y)
        test "$(git rev-parse refs/notes/m)" = "$(cat pre_merge_y)" &&
        # Verify that other notes refs has not changed (w, x, y and z)
@@ -466,7 +466,7 @@ EOF
        git notes merge --commit &&
        # No .git/NOTES_MERGE_* files left
        test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
-       test_cmp /dev/null output &&
+       test_must_be_empty output &&
        # Merge commit has pre-merge y and pre-merge z as parents
        test "$(git rev-parse refs/notes/m^1)" = "$(cat pre_merge_y)" &&
        test "$(git rev-parse refs/notes/m^2)" = "$(cat pre_merge_z)" &&
@@ -555,7 +555,7 @@ test_expect_success 'resolve situation by aborting the notes merge' '
        git notes merge --abort &&
        # No .git/NOTES_MERGE_* files left
        test_might_fail ls .git/NOTES_MERGE_* >output 2>/dev/null &&
-       test_cmp /dev/null output &&
+       test_must_be_empty output &&
        # m has not moved (still == w)
        test "$(git rev-parse refs/notes/m)" = "$(git rev-parse refs/notes/w)" &&
        # Verify that other notes refs has not changed (w, x, y and z)