rust/tests/ui/dyn-keyword/dyn-2015-idents-in-decl-mac...

53 lines
1.6 KiB
Rust

// Under the 2015 edition with the keyword_idents lint, `dyn` is
// not entirely acceptable as an identifier.
//
// We currently do not attempt to detect or fix uses of `dyn` as an
// identifier under a macro, including under the declarative `macro`
// forms from macros 1.2 and macros 2.0.
//
//@ check-pass
//@ edition:2015
#![feature(decl_macro)]
#![allow(non_camel_case_types)]
#![deny(keyword_idents)]
mod outer_mod {
pub mod r#dyn {
pub struct r#dyn;
}
}
// Here we are illustrating that the current lint does not flag the
// occurrences of `dyn` in this macro definition; however, it
// certainly *could* (and it would be nice if it did), since these
// occurrences are not compatible with the 2018 edition's
// interpretation of `dyn` as a keyword.
macro defn_has_dyn_idents() { ::outer_mod::dyn::dyn }
struct X;
trait Trait { fn hello(&self) { }}
impl Trait for X { }
macro tt_trait($arg:tt) { & $arg Trait }
macro id_trait($id:ident) { & $id Trait }
fn main() {
defn_has_dyn_idents!();
// Here we are illustrating that the current lint does not flag
// the occurrences of `dyn` in these macro invocations. It
// definitely should *not* flag the one in `tt_trait`, since that
// is expanding in a valid fashion to `&dyn Trait`.
//
// It is arguable whether it would be valid to flag the occurrence
// in `id_trait`, since that macro specifies that it takes an
// `ident` as its input.
fn f_tt(x: &X) -> tt_trait!(dyn) { x }
fn f_id(x: &X) -> id_trait!(dyn) { x }
let x = X;
f_tt(&x).hello();
f_id(&x).hello();
}