test_expect_success '--path=<path> complains without --textconv/--filters' '
sha1=$(git rev-parse -q --verify HEAD:world.txt) &&
test_must_fail git cat-file --path=hello.txt blob $sha1 >actual 2>err &&
- test ! -s actual &&
+ test_must_be_empty actual &&
grep "path.*needs.*filters" err
'