tests: don't fail the split --filter=CMD test if xz is not available

* tests/split/filter: Skip if xz is not installed.

diff --git a/tests/split/filter b/tests/split/filter
index 88321c0..1a7b06a 100755 (executable)
--- a/tests/split/filter
+++ b/tests/split/filter
@@ -18,6 +18,7 @@
 
 . "${srcdir=.}/init.sh"; path_prepend_ ../src
 print_ver_ split
+xz --version || skip_ "xz (better than gzip/bzip2) required"
 
 for total_n_lines in 5 3000 20000; do
   seq $total_n_lines > in || framework_failure_