tests/ui/higher-rank-trait-bounds/hrtb-opt-in-copy.rs

   1 // run-pass
   2 // Test that we handle binder levels correctly when checking whether a
   3 // type can implement `Copy`. In particular, we had a bug where we failed to
   4 // liberate the late-bound regions from the impl, and thus wound up
   5 // searching for an impl of `for<'tcx> Foo<&'tcx T>`. The impl that
   6 // exists however is `impl<T> Copy for Foo<T>` and the current rules
   7 // did not consider that a match (something I would like to revise in
   8 // a later PR).
   9
  10 #![allow(dead_code)]
  11
  12 use std::marker::PhantomData;
  13
  14 #[derive(Copy, Clone)]
  15 struct Foo<T> { x: T }
  16
  17 type Ty<'tcx> = &'tcx TyS<'tcx>;
  18
  19 enum TyS<'tcx> {
  20     Boop(PhantomData<*mut &'tcx ()>)
  21 }
  22
  23 #[derive(Copy, Clone)]
  24 enum Bar<'tcx> {
  25     Baz(Foo<Ty<'tcx>>)
  26 }
  27
  28 fn main() { }