Merge pull request #5979 from BenWiederhake/dev-shuf-null-input

shuf: Treat empty file as zero elements instead of one emptystring

tests/by-util/test_shuf.rs

@@ -48,6 +48,13 @@ fn test_zero_termination() {
     assert_eq!(result_seq, input_seq, "Output is not a permutation");
 }
 
+#[test]
+fn test_empty_input() {
+    let result = new_ucmd!().pipe_in(vec![]).succeeds();
+    result.no_stderr();
+    result.no_stdout();
+}
+
 #[test]
 fn test_echo() {
     let input_seq = vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10];