tests/ui/rfc-1445-restrict-constants-in-patterns/allow-hide-behind-direct-unsafe-ptr-embedded.rs

   1 // Test explores how `#[structral_match]` behaves in tandem with
   2 // `*const` and `*mut` pointers.
   3
   4 // run-pass
   5
   6 #![warn(pointer_structural_match)]
   7
   8 struct NoDerive(#[allow(unused_tuple_struct_fields)] i32);
   9
  10 // This impl makes NoDerive irreflexive
  11 // (which doesn't matter here because `<*const T>::eq` won't recur on `T`).
  12 impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }
  13
  14 impl Eq for NoDerive { }
  15
  16 #[derive(PartialEq, Eq)]
  17 struct WrapEmbedded(*const NoDerive);
  18
  19 const WRAP_UNSAFE_EMBEDDED: WrapEmbedded = WrapEmbedded(std::ptr::null());
  20
  21 fn main() {
  22     match WRAP_UNSAFE_EMBEDDED {
  23         WRAP_UNSAFE_EMBEDDED => { println!("WRAP_UNSAFE_EMBEDDED correctly matched itself"); }
  24         _ => { panic!("WRAP_UNSAFE_EMBEDDED did not match itself"); }
  25     }
  26 }