rust/tests/ui/parser/char/whitespace-character-literal.rs

// This tests that the error generated when a character literal has multiple
// characters in it contains a note about non-printing characters.

fn main() {
    let _hair_space_around = ' x​';
    //~^ ERROR: character literal may only contain one codepoint
    //~| NOTE: there are non-printing characters, the full sequence is `\u{200a}x\u{200b}`
    //~| HELP: consider removing the non-printing characters
    //~| SUGGESTION: x
}