src/test/ui/path-lookahead.rs

// run-pass
#![allow(dead_code)]
#![warn(unused_parens)]

// Parser test for #37765

fn with_parens<T: ToString>(arg: T) -> String {
  return (<T as ToString>::to_string(&arg)); //~WARN unnecessary parentheses around `return` value
}

fn no_parens<T: ToString>(arg: T) -> String {
  return <T as ToString>::to_string(&arg);
}

fn main() {

}