1// run-rustfix 2 3#![allow(unused_must_use)] 4#![warn(clippy::writeln_empty_string)] 5use std::io::Write; 6 7fn main() { 8 let mut v = Vec::new(); 9 10 // These should fail 11 writeln!(&mut v); 12 13 let mut suggestion = Vec::new(); 14 writeln!(&mut suggestion); 15 16 // These should be fine 17 writeln!(&mut v); 18 writeln!(&mut v, " "); 19 write!(&mut v, ""); 20} 21