Merge pull request #6011 from BenWiederhake/dev-shuf-repeat-zero-items

shuf: Refuse repeating zero lines

src/uu/shuf/src/shuf.rs

@@ -435,11 +435,10 @@ fn shuf_exec(input: &mut impl Shufable, opts: Options) -> UResult<()> {
  None => WrappedRng::RngDefault(rand::thread_rng()),
  };
 
- if input.is_empty() {
- return Ok(());
- }
-
  if opts.repeat {
+ if input.is_empty() {
+ return Err(USimpleError::new(1, "no lines to repeat"));
+ }
  for _ in 0..opts.head_count {
  let r = input.choose(&mut rng);
 

tests/by-util/test_shuf.rs

@@ -624,3 +624,32 @@ fn test_shuf_multiple_input_line_count() {
  .count();
  assert_eq!(result_count, 5, "Output should have 5 items");
 }
+
+#[test]
+#[ignore = "known issue"]
+fn test_shuf_repeat_empty_range() {
+ new_ucmd!()
+ .arg("-ri4-3")
+ .fails()
+ .no_stdout()
+ .stderr_only("shuf: no lines to repeat\n");
+}
+
+#[test]
+fn test_shuf_repeat_empty_echo() {
+ new_ucmd!()
+ .arg("-re")
+ .fails()
+ .no_stdout()
+ .stderr_only("shuf: no lines to repeat\n");
+}
+
+#[test]
+fn test_shuf_repeat_empty_input() {
+ new_ucmd!()
+ .arg("-r")
+ .pipe_in("")
+ .fails()
+ .no_stdout()
+ .stderr_only("shuf: no lines to repeat\n");
+}