git-check-attr: Add tests of command-line parsing

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t0003-attributes.sh

@@ -44,6 +44,13 @@ test_expect_success 'setup' '
 
 test_expect_success 'command line checks' '
 
+	test_must_fail git check-attr &&
+	test_must_fail git check-attr -- &&
+	test_must_fail git check-attr -- f &&
+	echo "f" | test_must_fail git check-attr --stdin &&
+	echo "f" | test_must_fail git check-attr --stdin -- f &&
+	echo "f" | test_must_fail git check-attr --stdin test -- f &&
+	echo "f" | test_must_fail git check-attr --stdin test f &&
 	test_must_fail git check-attr "" -- f
 
 '