#[diagnostic::on_unimplemented(message = "{{Test } thing")]
//~^WARN unmatched `}` found
//~|WARN unmatched `}` found
trait ImportantTrait1 {}

#[diagnostic::on_unimplemented(message = "Test {}")]
//~^WARN positional format arguments are not allowed here
//~|WARN positional format arguments are not allowed here
trait ImportantTrait2 {}

#[diagnostic::on_unimplemented(message = "Test {1:}")]
//~^WARN positional format arguments are not allowed here
//~|WARN positional format arguments are not allowed here
trait ImportantTrait3 {}

#[diagnostic::on_unimplemented(message = "Test {Self:123}")]
//~^WARN invalid format specifier
//~|WARN invalid format specifier
trait ImportantTrait4 {}

#[diagnostic::on_unimplemented(message = "Test {Self:!}")]
//~^WARN expected `'}'`, found `'!'`
//~|WARN expected `'}'`, found `'!'`
//~|WARN unmatched `}` found
//~|WARN unmatched `}` found
trait ImportantTrait5 {}

fn check_1(_: impl ImportantTrait1) {}
fn check_2(_: impl ImportantTrait2) {}
fn check_3(_: impl ImportantTrait3) {}
fn check_4(_: impl ImportantTrait4) {}
fn check_5(_: impl ImportantTrait5) {}

fn main() {
    check_1(());
    //~^ERROR {{Test } thing
    check_2(());
    //~^ERROR Test {}
    check_3(());
    //~^ERROR Test {1}
    check_4(());
    //~^ERROR Test ()
    check_5(());
    //~^ERROR Test {Self:!}
}