use syn::Type;
#[test]
fn test_mut_self() {
syn::parse_str::<Type>("fn(mut self)").unwrap();
syn::parse_str::<Type>("fn(mut self: ())").unwrap();
syn::parse_str::<Type>("fn(mut self: ...)").unwrap_err();
syn::parse_str::<Type>("fn(mut self: mut self)").unwrap_err();
syn::parse_str::<Type>("fn(mut self::T)").unwrap_err();
}