git tag c3
'
-test_expect_success 'merge c1 to c2' '
+merge_c1_to_c2_cmds='
git reset --hard c1 &&
git merge -s resolve c2 &&
test "$(git rev-parse c1)" != "$(git rev-parse HEAD)" &&
test 3 = $(git ls-files | wc -l)
'
+test_expect_success 'merge c1 to c2' "$merge_c1_to_c2_cmds"
+
+test_expect_failure 'merge c1 to c2, again' "$merge_c1_to_c2_cmds"
+
test_expect_success 'merge c2 to c3 (fails)' '
git reset --hard c2 &&
test_must_fail git merge -s resolve c3