| // Support for legacy derive helpers is limited and heuristic-based | |
| // (that's exactly the reason why they are deprecated). | |
| //@ edition:2018 | |
| //@ aux-build:test-macros.rs | |
| #[macro_use] | |
| extern crate test_macros; | |
| use derive as my_derive; | |
| #[my_derive(Empty)] | |
| #[empty_helper] // OK | |
| struct S1; | |
| // Legacy helper detection doesn't see through `derive` renaming. | |
| #[empty_helper] //~ ERROR cannot find attribute `empty_helper` in this scope | |
| #[my_derive(Empty)] | |
| struct S2; | |
| fn main() {} |