revision: implement sparse algorithm

diff --git a/t/t6120-describe.sh b/t/t6120-describe.sh
index a5d901502414f25616a474152ee0f5816465bd37..d639d946965547c86708701bfde276649c568a15 100755 (executable)
--- a/t/t6120-describe.sh
+++ b/t/t6120-describe.sh
@@ -121,10 +121,9 @@ test_expect_success 'describe --contains defaults to HEAD without commit-ish' '
        test_cmp expect actual
 '
 
-: >err.expect
 check_describe tags/A --all A^0
 test_expect_success 'no warning was displayed for A' '
-       test_cmp err.expect err.actual
+       test_must_be_empty err.actual
 '
 
 test_expect_success 'rename tag A to Q locally' '
@@ -378,4 +377,12 @@ check_describe tags/A --all A
 check_describe tags/c --all c
 check_describe heads/branch_A --all --match='branch_*' branch_A
 
+test_expect_success 'describe complains about tree object' '
+       test_must_fail git describe HEAD^{tree}
+'
+
+test_expect_success 'describe complains about missing object' '
+       test_must_fail git describe $ZERO_OID
+'
+
 test_done