tests/tail: Adjust tests for warnings of tail to use stderr_to_stdout

tests/by-util/test_tail.rs

@@ -3921,50 +3921,65 @@ fn test_args_when_settings_check_warnings_then_shows_warnings() {
  let scene = TestScenario::new(util_name!());
  let fixtures = &scene.fixtures;
 
- // TODO: mix stdout and stderr
- let expected_stdout = "file data\n";
- fixtures.write("data", expected_stdout);
+ let file_data = "file data\n";
+ fixtures.write("data", file_data);
 
- let expected_stderr = "tail: warning: --retry ignored; --retry is useful only when following";
+ let expected_stdout = format!(
+ "tail: warning: --retry ignored; --retry is useful only when following\n\
+ {}",
+ file_data
+ );
  scene
  .ucmd()
  .args(&["--retry", "data"])
+ .stderr_to_stdout()
  .run()
- .stderr_is(expected_stderr)
- .stdout_is(expected_stdout)
+ .stdout_only(expected_stdout)
  .success();
 
- let expected_stderr = "tail: warning: --retry only effective for the initial open\n";
+ let expected_stdout = format!(
+ "tail: warning: --retry only effective for the initial open\n\
+ {}",
+ file_data
+ );
  let mut child = scene
  .ucmd()
  .args(&["--follow=descriptor", "--retry", "data"])
+ .stderr_to_stdout()
  .run_no_wait();
 
  child
  .delay(500)
  .kill()
  .make_assertion()
  .with_current_output()
- .stderr_is(expected_stderr)
- .stdout_is(expected_stdout);
+ .stdout_only(expected_stdout);
 
- let expected_stderr = "tail: warning: PID ignored; --pid=PID is useful only when following";
+ let expected_stdout = format!(
+ "tail: warning: PID ignored; --pid=PID is useful only when following\n\
+ {}",
+ file_data
+ );
  scene
  .ucmd()
  .args(&["--pid=1000", "data"])
+ .stderr_to_stdout()
  .run()
- .stderr_is(expected_stderr)
- .stdout_is(expected_stdout)
+ .stdout_only(expected_stdout)
  .success();
 
- let expected_stderr = "tail: warning: --retry ignored; --retry is useful only when following\n\
- tail: warning: PID ignored; --pid=PID is useful only when following";
+ let expected_stdout = format!(
+ "tail: warning: --retry ignored; --retry is useful only when following\n\
+ tail: warning: PID ignored; --pid=PID is useful only when following\n\
+ {}",
+ file_data
+ );
  scene
  .ucmd()
  .args(&["--pid=1000", "--retry", "data"])
+ .stderr_to_stdout()
  .run()
- .stderr_is(expected_stderr)
- .stdout_is(expected_stdout)
+ .stdout_only(expected_stdout)
  .success();
 }